COMPUTER SECURITY
INDEX PAGE
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1. Definition/Scope of "COMPUTER SECURITY" 2
2. Why Should You Be Concerned? 2
3. Types of Security Breaches 3
4. Reasons for Exposure 7
5. General Security Rules (all computer systems) 8
6. Viruses: 9
6.1 History 9
6.2 Effect 10
6.3 Why do people do it? 10
6.4 Symptoms 10
6.5 Concerns 11
6.6 Known Virus Software (1) 11
6.7 Quick Guide to Virus Names (1) 12
6.8 Table of Virus Effects 16
6.9 Virus Detector/Antidote software 19
6.10 Trojan Horses 20
7. PC Rules of Thumb 22
8. Easy Tricks for PC Security 23
9. So You're Infected (Cure) 24
10. Summary: What Can You Do? 25
11. Security Policy: Points for Consideration 26
12. To run SCAN (included on this diskette) 29
(1) David Stang, Ph.D, "Network Security in the Federal Government,",
January, 1990, p.168-169 (updated by E.A.Bedwell, March, 1990)
- 2 -
Tonight's topic is "Computer Security," a subject near and dear to my
heart after catching fraud a few times, and cracking system security a
few times. The only unfortunate part of this evening is that I have
enough material to cover an intensive 2 or 3 day seminar and I only have
something over an hour, so in addition to extensive notes from this
presentation, I've put an article on viruses, and a PC virus detector
program on diskette for you.
1. SCOPE OF COMPUTER SECURITY
Computer security relates to any potential loss of information or your
ability to operate, regardless of the source of the problem. Of course,
all the publicity about computer security is going to the virus
situation. I don't want to dissuade anyone from their concerns about
viruses, because it's definitely a growing problem, and if you get hit,
you'll be sorry you ever laid eyes on a computer. But, current estimates
indicate that viruses represent only 3% of all the computer problems now
occurring. Of course, if you're one of the 3%, like CNIB or Barclay's
Bank Canada were last fall, you'll feel like you're the only one on
earth. The difference between viruses and other computer security issues
is apparently one of control: I hope to convince you that you have as
much control over viruses and as little control over the other 97% of
problems as to make them equal threats to the safety of your computer.
I'm going to get to viruses later, their prevention, detection and cure,
but I'd like first like to cover the other major problems that affect
computer security - the other 97% - and I'd like to start with reasons
why you should be concerned about security.
2. WHY SHOULD YOU BE CONCERNED?
Your data is a valuable asset, just like premises, equipment, raw
materials and inventory. Because so much of modern business depends on
computers - financial systems, engineering design, medical diagnosis,
production and safety control - the destructive potential is greater
every year. There has been more than one company that's suffered great
losses, and even gone under because of the loss of things like their
accounts receivable records: no one is going to pay you if you don't
send them a bill, and if they get word of your inability to invoice them,
their darned unlikely to volunteer payment - so you're in a financial
mess. The same goes for your design information, production data, the
consequences if safety control systems malfunction, or even the simple
loss of your customer list.
Another reason why you should be concerned is, too often, people don't
think about computer security until it's too late. There's a saying in
my industry that, "He who laughs last probably made a backup." Another
saying is, "Experience is something you don't get until just after you
needed it the most." Well, if it means the life of your company, or the
loss of potentially millions of dollars, or even just the information on
your home computer, it might be wise to get at least some basic knowledge
before the disaster strikes.
- 3 -
3. TYPES OF SECURITY BREACHES
Now that the 'why' is out of the way, let's break down the 97% of
problems. These are not in a specific order, but just as they came to
me. Nor have I attempted to attach percentages to each type of risk,
because very few computer crimes are actually reported, so any figures
that anyone could estimate would not be realistic:
FRAUD/THEFT
By far the biggest problem is fraud or theft. Some examples of this are:
CHAOS - 1987 - Hamburg -> NASA data bank info sold to USSR
Foreign exchange } famous because of big $
Electronic Funds Transfer } amounts, and because of the
Insider Trading } publicity they've received
Most common: Cookie jar technique - e.g., interest, income tax
(aka 'Salami' technique - take a little and no one
will notice)
Specific examples I've caught were in Payroll (no crash on < or =),
Accounts Payable (dummy companies), Purchasing (failed reasonableness
test), and Accounts Receivable (failed balance routine). These were all
thefts of money.
Another example of theft which is very interesting is the 28-year-old
Canadian who was arrested at UNISYS in Pittsburgh on Dec. 13/89 - what he
is alleged to have stolen was NCR's trade secrets - to the tune of
US$68M, which comes under a different Canadian law from monetary theft.
MALICIOUS DAMAGE / VANDALISM
The next major type of computer security breach is the disgruntled
employee syndrome. Their favourite is the logic bomb or time bomb: on a
certain date or condition after they leave the company, something's going
to happen, such as at the health centre in LA where all prescriptions
suddenly multiplied by 2. That's really serious, even compared to the
logic bomb that superzaps all your files off the face of the earth,
because someone could die. At least with a superzap, you can recover if
you've been backing up and have a disaster recovery plan in effect. Pure
physical vandalism occurs more often at educational institutions, but is
still a serious threat. I wouldn't let me near your machine if I was
angry with you - my vandalism would be difficult to detect (and expensive
to repair). A simple application of a magnetized screwdriver ......
LACK OF SECURITY PLANNING IN SYSTEM DESIGN STAGE
One of the biggest logic bombs that's going to occur is on January 1/2000.
Do you know how many computer systems use a 2 digit number for the year?
Do you know how much work it's going to be to adapt systems to recognize
00 as being greater than 99? My grandmother was born in 1886, and most
systems show her birth year as 99. If she lives to the year 1999, I
wonder if they'll start sending her the baby bonus. This time bomb is not
malicious damage, it's pure lack of planning at the system design stage.
- 4 -
(Lack of Security Planning - continued)
Things like balance checks and reasonableness tests are not built into the
system from the beginning, and it's not easy to put them in later. Users
must participate at the system design stage, because only they know what's
reasonable and what can be balanced. Don't expect a computer technician
to know everything there is to know about your job.
DISTORTED SENSE OF HUMOUR
Then there's the practical joker - the one who thinks it's funny to break
into the system to see what he can change, or create some dumb message to
appear on your screen. That's what happened at IBM when the infamous
Christmas tree appeared 2 years ago (1987). The joke was three-fold -
first it analyzed your electronic mail distribution lists and reproduced
itself to send to everyone you normally send messages to - this clogged
the system up with people reading more messages than normal. The second
part was a little more technical - everyone who read the message caused a
separate load of the offending program to take up space in memory, unlike
most systems where two or more people who are doing the same thing are
sharing one load of the software. This clogged memory up so that nothing
else could run. There was one more part to this: there were delay timers
built into the program so it deliberately ran very slowly. The result was
that the largest computer network in the world was shut down for 4 hours.
Someone must have had a great need for a power trip.
MISTAKE
Next, there's fumble fingers: you know, the one who keys the formula in
as 600 grams instead of 60 grams, or the estimated production time of 2
hours instead of 2 days. Or the one who almost took me into court when
he blamed "the computer" for a mistake. Without going into details about
that incident, I can say that going through the grilling by several
lawyers in a preliminary investigation was not the high point of my
career. What saved the situation (for me and the organization) was audit
trailing: every time a transaction was entered, the system recorded the
terminal i.d., the user i.d., the date and the time. It also saved a copy
of the record as it existed prior to the transaction taking place. A more
common mistake, though, is to unlatch a diskette door before the light
goes out. Few people realize that the FAT (file attributes table) is the
last thing written on a disk, and you can corrupt the FAT by removing the
disk too early.
"EVERYONE DOES IT" SYNDROME
Then there's everyone's favourite: copying software. Believe it or not,
in Canada, that falls under the Copyright law, not under theft, but it
has been successfully prosecuted. Even if you reverse engineer it and
make some minor changes, it will come under the "look and feel" test of
the Copyright law - if it looks and feels the same as the original, you
can be prosecuted. Copying software is illegal, and your company as the
registered owner could be held liable if it is detected.
- 5 -
ILLEGAL ACCESS
Many major computer crimes are perpetrated by illegal access: the 14-
year old who broke into NASA from his basement computer room is just one
example. There is password software on all larger machines, and it's not
difficult to put it on PCs. On the larger machines, one of the major
problems is not changing the standard passwords that are set when the
machine is delivered: the standard user-level password may be USER, the
standard operator password may be OPERATOR, and the standard field repair
person's password may be REPAIR, and so on. Guess how I've cracked
security a couple of times. In a 1988 article by Dr. Cliff Stoll in
"Computers and Security,", he reported that in 10 months of systematic
testing on computers attached to the US Defense Data Network (Milnet),
access was gained in 13% of the attempts simply by guessing at passwords!
There should be some rules applied to passwords: not less than 7 or 8
characters, must be changed at least every 60 days, don't use common
things like names (another way I've broken security), don't share it
under any circumstances and, for heaven's sake, don't post it on the
front of your machine or leave it where someone can find it. It's your
personal PIN - just like the money machine - and the information you're
dealing with is worth money. Some of the most difficult passwords to
break (take it from me) are "two words reversed" (e.g., boardwall,
hornshoe, cuptea), or foreign language words (e.g., coupdegrace,
millegrazie, caliente). Nonsense is good, too: geebleurql is nice.
If you're installing password security on a PC, consider whether you
should have it so tight that there is no recourse to the DOS level or no
ability to boot from the A: drive. You'd need really good password
software (or a good technician on staff) if you have both of these
facilities - otherwise you can lock yourself out - but it's my preference
(especially for the guy who's wiped his root directory twice).
PHYSICAL SECURITY
Finally, another area that affects computer security or your ability to
carry on computer operations, and one that is often overlooked, is simple
physical security: keys, thermal shock, vibration, dirt, water, fire,
visibility of information, steady power supply, discharge of static
electricity, magnetic fields, are all relevant to security. We have one
man in our network who should have (a) cabling bolted to his computer and
the floor, (b) a key to his unit, and (c) dust protectors (as well as
password access only without recourse to the DOS level).
When it comes to thermal shock, if you work in an area where the heat is
reduced on winter weekends, I strongly recommend you leave your unit
running over the weekend - just lock the keyboard. If the air
conditioning is shut down, turn your unit off, and don't turn it on until
the temperature is 23C or less. And please don't leave your machine
sitting in the sun, or in front of an open window to attract dust. The
internal temperature raises within 20 mins. or so to >30C, and the effects
of thermal shock are such that it can, first, rock memory chips out of
their sockets, and, worse, misalign the read heads on your disk drive so
that nothing can be read.
- 6 -
(Physical Security - continued)
Vibration, too, is a source of problems, especially for drives. The read
heads actually float over the surface of drives, not on them the way a
record player needle does, and the space tolerance between is measured in
Angstroms (metric version of microinches). Vibration can cause the head
to hit the drive, and you can say goodbye to whatever was written there.
If you're in a particularly sensitive field, and your information is what
might be called top secret to your company, you might also want to look
at two protection devices: one is encryption, and the other is Tempest
hardware or shielding. Encryption involves translating your data using
algorithms to something unreadable, and de-coding it when you need it. It
uses a "key" to choose the algorithm - dont' lose the key! It comes in a
few forms: software controlled encryption, hardware based encryption, or
a combination of the two. Most encryptors work with standard algorithms,
but defense departments and other high-security installations prefer
random algorithms. Tempest hardware, or shielding, protects against
sniffing of signals. ( Signal emanation surveillance is called
"sniffing.") I don't have a computer here to demonstrate this, but if
you take an old battery-operated transistor radio and set the dial to the
bottom of the AM band around 520, try passing it within a foot of your
computer. Your ear might not pick up the individual signals, but I assure
you there's equipment that does. That's why the US Army was blasting rock
music around the Vatican Embassy when Noriega was there - to mask signals.
More important to the average user, though, is avoidance of electro-
magnetic fields (such as ringing phones near a disk or disk drive), and
having an automatic disk head 'parker' that moves the heads to a safe zone
every few seconds. That way, something like a brief power failure is less
likely to cause a "head crash" on the disk.
Simple visibility of information is a risk. Recently I went to a bank
with a court order in hand to give me access to an account. The clerk
simply turned the terminal toward me and, if I'd wanted to bother, I could
have had the account numbers of two other people with identical names.
There is screen saving software that will blank your screen after an
inactivity duration you choose, and personnel should be made conscious
that unauthorized viewing of information is a security risk. And watch
what your staff throw out on paper, too.
When it comes to fire and water, there are two basic rules that everyone
can follow: first, don't smoke around the PC, and second, don't feed the
PC coffee and donuts. You might be able to save a keyboard or some parts
with a bath in distilled water, possibly followed by drying with a warm
hair dryer, but there's no guarantee. I prefer pure isopropyl alcohol -
without the hairdryer so I don't get fried in the process. Don't blast a
computer with a fire extinguisher if you can avoid it. If you do have a
fire or a flood, though, you'd better have a tested disaster recovery
plan, and your backups stored off-site.
All of these issues are reasonably within your control: fraud, theft,
disgruntled employees, practical jokers, fumble fingers, software copying
and physical security, at least as much as the infamous viruses that are
around, but let's take a look at why you're at risk.
- 7 -
4. REASONS FOR EXPOSURE
Concentration of data in one place
Instantaneous adjustment
Alteration without a trace
Lack of visible records
Complexity of the system
Networking
Technical persons can befuddle
General ignorance by non-techie and management
Detection problems
Lack of training
Security checks in programs not specified
Systems not documented
Limited staff resource for programming/management
No separation of duties
Possibility of enormous losses remaining undetected
Reluctance to report - Embarrassment
Lack of sufficient evidence to prosecute
Cost to prosecute outweighs recovery
Company policy ("Press would have a field day")
- 8 -
5. GENERAL SECURITY RULES (All Systems, big and small)
Disaster Recovery } Backup Backup Backup
Plan } Restore (test it to make sure it works)
Store your backup off-site (not in your car!)
Physical security
Password for access control (don't stick your password on
the front of your machine!)
Access to menu only - not to system control level
Reasonableness tests
Balance checks (rounding: up, down, (out?); cross-calculations
Audit trails - all records (terminal i.d., user i.d., date and
time stamping, history record retention)
Fall-through coding (if it doesn't meet a condition, does it go to limbo)
Payroll/Accounts payable: don't pay the same # twice
Fault tolerance level supported (user friendly/hostile -
balance between fault tolerance & productivity)
Call back or no answer on dial-up systems
UPS (Uninterrupted Power Supply, or allowance for graceful
degradation) - or at least an automatic head parker
Logical view rights (your user 'privileges' allows access only to the
data you need to see, e.g., accounting clerks don't need to see
production formulae)
Multi-user environment: protection against deadly embrace
Automatic logoff on inactivity timer / Screen saver
Policy statement re purchasing/use/theft/illegal
software, etc.
Encryption (?) - don't lose the key!
Shielding ("Tempest" hardware for secure systems)
Educate users
- 9 -
6. VIRUSES
As in medicine, a virus needs an 'organism' to which it may attach itself,
and a virus is 'contagious'.
In the case of computers, a virus is usually a destructive piece of code
which attaches to a working program, such as your word processor,
spreadsheet or CAD/CAM software. Viruses are usually written to detect
any load of a computer file that has an extension of .EXE, .COM, .OVL,
.BIN - such extensions representing executable programs. Often, the
virus loads itself into memory, then loads the program you just called, so
the virus is sitting at the front. Then when you exit the program, the
virus code calls for the re-writing of the program back onto the disk -
with the virus still sitting at the front. Other viruses simply go
straight into your boot sector, so they get loaded every time you turn on
your machine. Some do both.
However they 'hide', and whatever they attach to, they got to your machine
on an infected diskette. If you are infected and then copy your software
to use on another machine, guess what happens? Right! That's where the
'contagious' element comes in.
In 1989, more viruses were discovered than in all previous years. There
were over 110 at the end of the year, and 7 were discovered in December
alone. Sources have been from as far away as Pakistan and Bulgaria.
Only .004% have reported infections, but most are not reported. Consider
this: if only 1% were infected, that would be 1/2 million units in the
U.S. alone. At a cost ranging from $300 to $3,000 per unit to recover,
the problem starts to impact the economy as well as the productivity of
staff at your organization. It cost one Texas company US$10M to shut
down their 3,000-unit network for 4 days to find 35 infected units.
One of the major problems with viruses is that 90% of the users who
recover are re-infected within 30 days. One person at my organization
was re-infected 7 times in 2 months! Most reinfections occur for one of
two reasons (not necessarily in this order): your back-up was infected,
or it was a virus that hid in the boot sector on track 0, and track 0 is
not re-written by the standard "FORMAT" command (only a low-level format
will get rid of a track 0 virus). Be careful of some new software as
well: there has been more than one instance of shrink-wrapped software
being infected (software companies have disgruntled employees, too, it
seems).
6.1 HISTORY
1959 - Scientific American article about 'worms'
1963 - caught my first two frauds (Payroll & Accounts Payable)
1970 - Palo Alto lab - worm which directed activities
1982 - Anonymous Apple II worm
1984 - Scientific American CoreWare Series: held contest to
find the most clever/difficult to detect 'bug'
1987 - Apparent change from intellectual exercise to
dangerous activity.
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6.2 EFFECT
Massive destruction: Reformatting
Programs erased
Data file(s) modified/erased
Partial/Selective destruction: Modification of data/disk space
File allocation tables altered
Bad sectors created
If match with event, alter or delete
Random havoc: Altering keystroke values
Directories wiped out
Disk assignments modified
Data written to wrong disk
Annoyance: Message
Execution of RAM resident programs
suppressed
System suspension
6.3 WHY DO PEOPLE DO IT?
Financial gain
Publicity
Intellectual exercise
Terrorism/Fanaticism/Vandalism
Revenge
Just plain wierd
6.4 SYMPTOMS
Change in file size (Usually on .COM, .EXE
.OVL, .BIN, .SYS or .BAT files)
Change in update time or date
Common update time or date
Decrease in available disk or memory space
Unexpected disk access
Printing and access problems
Unexpected system crashes
- 11 -
6.5 CONCERNS
Variety: Virus vs Bug vs Worm vs Trojan Horse vs Superzapper
vs Trap Doors vs Piggybacking vs Impersonation
vs Wiretapping vs Emulation
Strains / Complexity / Growing Sophistication
Bulletin board use and free software
Largest threats from taking computer work home
Kids using same machine at home
Networked mainframe systems
Travel/airline computers (AA wiped out early 1989)
Work message systems (E-Mail)
POS terminals
Banking / Credit Cards / Money Machines
Income Tax records
Health records
**************************************************************
* Global disaster may be on the way *
* No specific laws to deal with malicious programming *
* No single national centre to gather data on infections *
**************************************************************
6.6 KNOWN VIRUS SOFTWARE
12 viruses (and their strains) account for 90% of all PC infections:
_
|_| Pakistani Brain
|_| Jerusalem
|_| Alameda
|_| Cascade (1701/1704)
|_| Ping Pong
|_| Stoned
|_| Lehigh
|_| Den Zuk
|_| Datacrime (1280/1168)
|_| Fu Manchu
|_| Vienna (DOS 62)
|_| April First
- 12 -
6.7 QUICK GUIDE TO VIRUS NAMES (Cross referenced)
Name Synonym-1 Synonym-2 Synonym-3 Synonym-4
1168 Datacrime-B
1184 Datacrime II
1280 Datacrime Columbus Day October 12th Friday 13th
1536 Zero Bug
1701/1704 Cascade Falling Letters Falling Tears Autumn Leaves
1704 Cascade
1704 Cascade-B
1704 Cascade-C
1704 Cascade-D
1704 Format 1704 Blackjack Falling Letters
1704 Blackjack 1704 Format Falling Letters
1808 Jerusalem Black Box/Hole Israeli PLO 1808/1813
1813 Jerusalem Black Box/Hole Israeli PLO 1808/1813
2086 Fu Manchu
2930
3066 Traceback
3551 Syslock
3555
123nhalf
405
500 Virus Golden Gate
512 Virus Friday 13th COM virus
648 Vienna DOS 62 DOS 68 Austrian
AIDS VGA2CGA Taunt
AIDS Info Disk
Alabama
Alameda Virus Yale Merritt Peking Seoul
Alameda-B Sacramento Yale C
Alameda-C
Amstrad
Anti
Apple II GS LodeRunner
April 1st SURIV01 SURIV02
April 1st-B
Ashar
Austrian 648 Vienna DOS 62 DOS 68
Australian Stoned New Zealand Marijuana
Autumn Leaves Cascade 1701/1704 Falling Letters Falling Tears
Basit virus Brain Pakistani Brain Lehore
Black Box Jerusalem Israeli Black Hole 1808/1803 PLO
Black Hole Jerusalem Black Box Israeli 1808/1813 PLO
Black Hole Russian
Blackjack 1704 1704 Format Falling Letters
Bouncing Ball Vera Cruz Ping Pong Bouncing Dot Italian virus
Bouncing Dot Italian virus Bouncing Ball Vera Cruz Ping Pong
Brain-B Brain-HD Harddisk Brain Houston virus
Brain-C
Brain-HD Harddisk Brain Houston virus Brain-B
- 13 -
Brain Pakistani Brain Basit virus Lehore
Cascade 1701/1704 Falling Letters Falling Tears Autumn Leaves
Cascade(-B-C-D) 1704
Century Oregon Jan.1, 2000
Century-B
Chroma
Clone
Clone-B
Columbus Day 1280/Datacrime October 12th Friday 13th
COM virus 512 virus Friday 13th
COM-B Friday 13th-B
COM-C Friday 13th-C
Cookie virus Sesame Street
Dark Avenger
Datacrime 1280
Datacrime-B 1168
Datacrime-II 1184
dBASE virus
Den Zuk Search Venezuelan
Disk Killer Ogre
Do-Nothing (don't believe it!)
DOS-62 Vienna DOS-68 648 Austrian
DOS-68 Vienna DOS-62 648 Austrian
DOS-62 UNESCO
DOS-62-B
Falling Tears Cascade 1701/1704 Falling Letters Autumn Leaves
Falling Letters 1704 Blackjack 1704 Format
Falling Letters Cascade 1701/1704 Falling Tears Autumn Leaves
Falling Letters-Boot Ping Pong B
Fat 12 Swap Israeli Boot
FluShot4 (a corrupted version of a virus detector - use FluShot4+)
Friday 13th 1280/Datacrime Columbus Day October 12th COM
Friday 13th-B COM-B 512
Friday 13th-C COM-C
Fumble Type
Fu Manchu 2086
Ghost-Boot
Ghost-COM
Golden Gate 500 Virus
Golden Gate -B
Golden Gate-C Mazatlan
Golden Gate-D
Harddisk Brain Brain-B Brain-HD Houston virus
Holland Girl Sylvia
Houston virus Brain-B Brain-HD Harddisk Brain
Icelandic Disk-Crunching-virus Saratoga 2
Icelandic 1 Saratoga 1
Icelandic 2 System virus
INIT29
IRQ v. 41
Israeli Friday13 Jerusalem Black Box/Hole 1808/1813 PLO
Israeli Boot Swap Fat 12
- 14 -
Italian virus Bouncing Ball Vera Cruz Ping Pong Bouncing Dot
Jan.1, 2000 Century Oregon
Jerusalem Israeli Black Box/Hole 1808/1813 PLO Friday 13th
Jerusalem-B New Jerusalem
Jerusalem-C
Jerusalem-D
Jerusalem-E
Jork
Key
Lehigh
Lehigh-2
Lehore Brain Pakistani Brain Basit
Lisbon
LodeRunner Apple II GS
MacMag Peace virus
Madonna (while the nice music plays, your hard disk is being destroyed)
Mailson
Marijuana New Zealand Stoned
Mazatlan Golden Gate-C
Merritt Alameda virus Yale Peking Seoul
Mix1
Music virus Oropax virus
New Jerusalem Jerusalem-C
New Zealand Stoned Marijuana Australian
New Zealand-B Stoned-B
New Zealand-C Stoned-C
nVIR
October 12th 1280/Datacrime Columbus Day Friday 13th
Ohio
Ogre Disk Killer
Oregon Century
Oropax virus Music virus
Pakistani Brain Lehore Basit Brain
Palette Zero Bug
Payday
Peace Virus MacMag
Pearson
Peking Alameda virus Yale Merritt Seoul
Pentagon
Ping Pong Bouncing Dot Italian virus Bouncing Ball Vera Cruz
Ping Pong-B Falling Letters-Boot
PLO Jerusalem Friday 13th 1808/1813 Israeli
Russian Black Hole
Sacramento Alameda-B Yale C
Saratoga 1 Icelandic 1
Saratoga 2 Icelandic Disk-Crunching-virus
Scores
Search Den Zuk Venezuelan
Seoul Alameda virus Yale Merritt Peking
Sesame Street Cookie virus
SF virus
Shoe virus UIUC virus (see also Terse Shoe)
- 15 -
Shoe virus-B
Stoned New Zealand Marijuana Australian
Stoned-B New Zealand-B
Stoned-C New Zealand-C
SUMDOS
Sunday
SRI (destroys anti-viral programs before it damages your system)
SURIV01 April 1st
SURIV02 April 1st
SURIV03
Swap Israeli Boot Fat 12
Sylvia Holland Girl
SYS
Syslock 3551
System virus Icelandic 2
Taunt AIDS VGA2CGA
Terse Shoe (see also Shoe virus)
TP04VIR Vacsina
TP25VIR Yankee Doodle
TP33VIR Yankee Doodle
TP34VIR Yankee Doodle
TP38VIR Yankee Doodle
TP42VIR Yankee Doodle
TP44VIR Yankee Doodle
TP46VIR Yankee Doodle
Traceback 3066
Typo (boot)
Typo (COM) Fumble
UIUC virus Shoe virus
UNESCO DOS-62
Venezuelan Den Zuk Search
Vera Cruz Ping Pong Bouncing Dot Italian Virus Bouncing Ball
Vacsina TP04VIR
VGA2CGA AIDS Taunt
Vienna DOS-62 DOS-68 648 Austrian
Vienna-B
Yale Alameda virus Merritt Peking Seoul
Yale C Alameda-B Sacramento
Yankee Doodle TP25VIR
Yankee Doodle TP33VIR
Yankee Doodle TP34VIR
Yankee Doodle TP38VIR
Yankee Doodle TP42VIR
Yankee Doodle TP44VIR
Yankee Doodle TP46VIR
Zero Bug 1536
- 16 -
6.8 TABLE OF VIRUS EFFECTS (by virus name)
This information is a reformatted version of that which was made
available to the writer by the National Computer Security Association,
Suite 309, 4401-A Connecticut Ave. NW, Washington, D.C., 20008.
This list is not as complete as the list of names preceding. Since
viruses must be created and caught before they can be analyzed for the
type of information that follows, this list will never be as complete as
the list of names. In some instances, you may have been infected with a
variation of the name. You might wish to check this list for all
possible variations of a name you've found on the list of synonyms.
Explanation of codes used under "What it does", and analysis of frequency
of occurrence of each effect:
EFFECT # OCCURRENCES %
------ - ----------- -
1. Virus uses self-encryption 13 12
2. Virus remains resident 83 74
3. Infects COMMAND.COM 8 7
4. Infects .COM files 62 55
5. Infects .EXE files 41 37
6. Infects .OVL files 15 13
7. Infects floppy disk boot sector 36 32
8. Infects hard disk boot sector 14 13
9. Infects partition table 1 1
10. Corrupts or overwrites boot sector 31 28
11. Affects system run-time operation 53 47
12. Corrupts program or overlay files 57 51
13. Corrupts data files 4 4
14. Formats or erases all/part of the disk 17 15
15. Corrupts file linkage (FAT) 9 8
16. Overwrites program 4 4
17. Mac virus (as opposed to PC virus) 2 2
Increase in Disinfector
VIRUS NAME Prog'm size that works What it does
---------- ----------- ----------- ------------
1168/Datacrime B 1168 SCAN/D 1, 4, 12, 14
1184/Datacrime 2 1184 1, 4, 5, 12, 14
123nhalf 3907 2, 5, 11, 13
1280/Datacrime 1280 SCAN/D 1, 4, 12, 14
1514/Datacrime II 1514 SCAN/D 1, 4, 5, 12, 14
1536/Zero Bug 1536 SCAN/D 2, 4, 11, 12
1701/Cascade 1701 M-1704 1, 2, 4, 11, 12
1704/Format 1704 M-1704 1, 2, 4, 11, 12, 14
1704/Cascade 1704 M-1704 1, 2, 4, 11, 12
1704/Cascade-B 1704 M-1704 1, 2, 4, 11, 12
1704/Cascade-C 1704 1, 2, 4, 11, 12
1704/Cascade-D 1704 1, 2, 4, 11, 12
2930 2930 SCAN/D 2, 4, 5, 12
- 17 -
3066/Traceback 3066 M-3066 2, 4, 5, 12
3551/Syslock 3551 SCAN/D 1, 4, 5, 12, 13
3555 3555 1, 3, 4
405 SCAN/D 4, 16
AIDS SCAN/D 4, 16
AIDS Info Disk 0 AIDSOUT 11
Alabama 1560 SCAN/D 2, 5, 11, 12, 15
Alameda-B 2, 7, 10
Alameda-C 2, 7, 10
Alameda/Yale MDISK 2, 7, 10
Amstrad 847 SCAN/D 4, 12
April 1st 2, 4, 11
April 1st-B 2, 5, 11
Ashar MDISK 2, 7, 10
Black Hole 1808 2, 4, 5, 6, 11, 12, 15
Brain-B 2, 7, 8, 10
Brain-C 2, 7, 8, 10
Century 2, 4, 5, 6, 11, 12, 14, 15
Century-B 2, 4, 5, 6, 11, 12, 14, 15
Clone-B 2, 7, 10, 15
Clone virus 2, 7, 8, 10
dBASE 1864 SCAN/D 2, 4, 11, 12, 13
DOS-62-B 3, 4, 11
DOS-62-UNESCO 650 3, 4, 11
Dark Avenger 1800 M-DAV 2, 3, 4, 5, 6, 11, 12, 15
Datacrime II-B 1917 SCAN/D 1, 3, 4, 5, 12, 14
Disk Killer MDISK 2, 7, 8, 10, 11, 12, 13, 14
Do-Nothing 608 SCAN/D 4, 12
Fri 13th COM 512 SCAN/D 4, 12
Fri 13th COM-B 512 4, 12
Fri 13th COM-C 512 4, 12
Fu Manchu 2086 SCAN/D 2, 4, 5, 6, 11, 12
Ghost-Boot ver. MDISK 2, 7, 8, 10, 11
Ghost-COM ver. 2351 SCAN/D 4, 10, 12
Golden Gate 2, 7, 10, 14
Golden Gate-B 2, 7, 10, 14
Golden Gate-C 2, 7, 10, 14
Golden Gate-D 2, 7, 10, 14
IRQ v. 41 4, 5, 11
Icelandic I 642 SCAN/D 2, 5, 11, 12
Icelandic II 661 SCAN/D 2, 5, 11, 12
Italian/Ping Pong MDISK 2, 7, 10, 11
Italian-B MDISK 2, 7, 8, 10, 11
Jerusalem 1808 SCAN/D/A 2, 4, 5, 6, 11, 12
Jerusalem-B 1808 M-JERUSLM 2, 4, 5, 6, 11, 12
Jerusalem-C 1808 2, 4, 5, 6, 11, 12
Jerusalem-D 1808 2, 4, 5, 6, 11, 12
Jerusalem-E 1808 2, 4, 5, 6, 11, 12, 15
Jork 2, 7, 10
Lehigh SCAN/D 2, 3, 12, 14, 16
Lehigh-2 2, 3, 12, 14, 15, 16
Lisbon 648 SCAN/D 4, 12
- 18 -
MIX1 1618 SCAN/D 2, 5, 11, 12
New Jerusalem 1808 M-JERUSLM 2, 4, 5, 6, 11, 12
New Zealand MD 7
New Zealand-B 7, 8
New Zealand-C 7, 8
nVIR 11, 17
Ohio MDISK 2, 7, 10
Oropax 2, 4
Pakistani Brain MDISK 2, 7, 10
Palette/Zero Bug 1536 2, 3, 4,
Payday 1808 M-JERUSLM 2, 4, 5, 6, 12
Pentagon MDISK 7, 10
SF Virus 2, 7, 11, 14
SRI 1808 2, 4, 5, 6, 11, 12
SURIV01 897 SCAN/D 2, 4, 11, 12
SURIV02 1488 SCAN/D 2, 5, 11, 12
SURIV03 SCAN/D 2, 4, 5, 6, 11, 12
SYS 2, 7, 8, 11, 12
SYS-B 2, 7, 8, 11, 12
SYS-C 2, 7, 8, 11, 12
Saratoga 632 SCAN/D 2, 5, 11, 12
Saratoga-2 2, 5, 11, 12
Scores 11, 17
Search HD 2, 7, 8, 10, 11
Search-B 2, 7, 10, 11
Search/Den Zuk MDISK 2, 7, 10, 11
Shoe virus 2, 7, 8, 10
Shoe virus-B 2, 7, 10
Stoned/Marijuana MDISK/P 2, 7, 9, 10, 11, 15
SumDOS 1500 4, 5, 14
Sunday 1636 SCAN/D 2, 4, 5, 6, 11, 12
Swap/Israeli Boot MDISK 2, 7, 10
Sylvia/Holland 1332 SCAN/D 2, 4, 12
Terse Shoe virus 2, 7, 10
Typo (Boot) MDISK 2, 7, 8, 10, 11
Typo/Fumble (COM) 867 SCAN/D 2, 4, 11, 12
Vacsina/TP04VIR 2, 4, 5
Vienna-B 648 SCAN/D 2, 4, 5, 12
Vienna/648 648 M-VIENNA 4, 12
Yankee Doodle 2855 SCAN/D 2, 4, 5, 11, 12
Yankee Doodle/TP25VIR 2, 4, 5
Yankee Doodle/TP33VIR 2, 4, 5
Yankee Doodle/TP34VIR 2, 4, 5
Yankee Doodle/TP38VIR 2, 4, 5
Yankee Doodle/TP42VIR 2, 4, 5
Yankee Doodle/TP44VIR 2, 4, 5
Yankee Doodle/TP46VIR 2, 4, 5
- 19 -
6.9 VIRUS DETECTOR AND ANTIDOTE SOFTWARE
*** None offer complete protection ***
Some do NOT test for boot sector viruses, modification of the command
interpreter, branching into the BIOS, etc., unconventional things that
nasty viruses are known to do. This is not a comprehensive list, but
you'll have an idea of what's available, either commercially or through
public domain. Look for a product that will detect as many of the
effects identified in the previous section as possible. Warning: some
highly publicized virus detectors only search for ONE (1) virus! Others
are more sophisticated, and may even act as a disinfector as well as a
detector.
Old virus symptoms vs file changes
Antidote
Antigen
Bombsqad
Canary
Cylene-4
C-4
Disk Defender * recommended (add-on board - write-protects hard disk)
Disk watcher
Dr. Panda Utilities
IBM - COMPare in DOS
Mace vaccine
Magic Bullets
Syringe
Sentry * recommended for systems booted regularly
Vaccine
Viraid
Virus-Pro * recommended for large corporate environments
Shareware: Novirus
Flushot4+
Virusck
Viruscan
Plus what's shown on preceding pages as a "Disinfector that works". I
also have a list of over 100 shareware products that do everything from
detect and/or disinfect to write-protecting the hard drive and requiring
password access .... but my fingers are getting tired from typing at this
point, and there are more important things to cover - after all, if
you're careful, you won't need a list of detectors/disinfectors.
- 20 -
6.10 TROJAN HORSES
While a "virus" is something hidden within another program that is
waiting to make your system really sick, and a "worm" may be something
that lives on its own and usually transmits through networked computers,
a "Trojan Horse" is a little of both, so I've included it with this virus
section if only to warn you of its existence. It lives on its own as a
program, and will bring you down like Helen of Troy's soldiers. "I
wouldn't copy something like that," you say. Well, like Helen's horse,
it comes disguised. It will purport to do something really neat, like
compress files (so you have more disk space available), sort your
directories (so you can find things more easily), or play chess or
another game with you. In actuality, it's really just waiting to do the
things that viruses do - trash your files, scramble your boot sector, fry
your FAT, or erase your hard disk. It doesn't usually do anything it
promises to do.
The following are just a few examples of the known Trojan Horses, most
of which come from bulletin boards. Please don't misunderstand me, most
BB operators are honest people who are trying to help the computer
industry as a whole, but they can't be held responsible for the people
who might dial into their BB and leave a disaster waiting until the next
caller(s).
SCRNSAVE.COM: This is supposed to blank your screen after x seconds of
inactivity, thus preventing image burn-in or apparently
offering a sense of security; say goodbye to your files
while it erases your harddisk.
TSRMAP: For the 'sophisticated' user who uses Terminate and Stay
Resident programs, it's sometimes handy to have a map of
where these programs are loaded in memory, and be able to
delete some if you're short of memory; hopefully this
same 'sophisticated' user has a copy of track 0, because
his was just sent to heaven ..... or elsewhere.
DOS-HELP: Sounds great, doesn't it? This TSR program is supposed to
give on-line help on DOS commands. Your hard disk was
just formatted.
ULTIMATE.EXE: This is supposed to be a DOS shell (if you've used
Directory Scanner or some other software that allows you
to move around directories and load programs easily, or
even a menu system, then you know what a DOS shell is).
While the "Loading..." message shows on your screen, the
FAT (file allocation table) of your hard disk went to the
trash bin.
BARDTALE.ZIP This purports to be a commercial game from Electronic Arts
(BARDTALE I) Someone reverse engineered this program, and
wrote in a routine to format your hard disk upon
invocation.
- 21 -
COMPRESS.ARC This is dated April 1 1987, is executed from a file named
RUN-ME.BAT, and is advertised as "shareware from Borland"
(Borland is a highly reputable company). It will not
compress your files, but it will very competently destroy
your FAT table.
DANCERS.BAS You'll actually see some animated dancers in colour -
while your FAT is being tromped on.
DEFENDER.ARC Think you're going to get a copy of Atari's DEFENDER for
nothing, huh? There's still no such thing as a free
lunch, and this one will be particularly expensive: it
not only formats your hard disk, but it writes itself to
your ROM BIOS - the chip that holds the Basic Input Output
System for your machine. Get your wallet out.
SIDEWAYS.COM The good "SIDEWAYS.EXE" is about 30Kb, while this version
is about 3Kb. The really big difference, though, is what
happens to your hard drive - it's spun off into oblivion.
These are only a few of the 70 or so Trojans I have listed at work, but
I'm sure you've got the idea. These programs (a) stand alone, (b) often
claim to do something useful, (c) may be hacked versions of good
software, (d) may be named the same as good software, (e) may send you
back to using a quill pen.
- 22 -
7. PC RULES OF THUMB (Additional to Basic Rules of Thumb)
Run virus check BEFORE backup
Boot floppy systems from known, protected disks only
Never work with masters - first make copies on a trusted machine
Store data on floppy:
set path in autoexec.bat, but load from A: to
ensure data goes to floppy
Save your data periodically while working
Use write protect tabs
Use write protect software on hard disk / backup track 0
Never boot HD systems from floppies (unless known and
protected)
New/repaired hard disk? - run a virus detector
Use protection package (practice safe hex)
Avoid shareware / BB demos
if you use a BB, set path to A: beforehand,
download only to A:, poweroff immediately after,
then powerup and do a virus scan on the floppy;
always scan shareware
Know the source of your software
Don't use illegal copies
If your data is truly confidential, don't depend on
DELETE - you must use, e.g., Wipefile
Autopark software
Hardcards
- 23 -
6. A FEW EASY TRICKS FOR PC SECURITY
1. Set Read only attributes on all files ending with .COM, .EXE, .SYS,
. OVL, .BIN, .BAT
e.g.: ATTRIB +R *.SYS
2. Use an undocumented trick in DOS of naming your data files ending
with an ASCII blank or NUL character (ASCII 32 or 255): ***
e.g.: COPY A:OLDFILE.TXT NEWFILECHR$(255).TXT
or REN A:MYFILE.DAT MYFILECHR$(32).DAT
*** Newer versions of DOS will give the ASCII blank or null by
holding the [Alt] key and striking the numeric keypad numbers;
e.g. COPY A:OLDFILE.TXT NEWFILE[Alt]255
3. Prevent inadvertent formatting of the hard disk:
Rename FORMAT.EXE to (e.g.) DANGER.EXE
Write a 1-line batch file called FORMAT.BAT:
DANGER A: %1 %2 %3 %4 %5 %6
4. Have a batch program as a shutdown routine, to run:
1. Virus Check
2. Copy Track 0
3. Back up your data files
4. Park the heads
- 24 -
9. SO YOU'RE INFECTED
Terminate all connections with other computers
Record your last activities
Determine the nature and extent of the damage
Notify other users
Contact the source of the carrier software
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Back up data files to new diskettes
Erase infected disk (using high or low level format -
low level is preferred to re-write track 0)
Check master disks with detection program(s)
Restore system files
Restore data files
Run detection program(s) again
Be careful in future - think like a thief!
------------------
- 25 -
10. SUMMARY: WHAT CAN YOU DO?
There are many aspects to computer security, none of which are totally
within your control, but all of which are reasonably within your control.
One of the major methods of getting control is to establish an
enforceable security policy AND a disaster recovery plan. However, it's
almost impossible to establish a plan unless you first know what the
risks are.
WHEN YOU GO BACK TO YOUR OFFICE
Try putting some staff into two teams: "hackers" and "police" (or call
them Blue Jays and Cardinals if you find that offensive). The role of
the hackers is to try to dream up all the things they could get from or
do to the company (or to a department) by breaking computer security.
The role of the police is to respond with defenses. Then switch roles.
List all the ideas, no matter how "far out" they seem, then use this for
the basis of risk analysis and disaster recovery planning. The only rule
to this game is that no idea is initially rejected.
Now that you have some idea of the value of your data and the risks it is
under, you can begin to work on a "Computer Security Policy" and a
"Disaster Recovery Plan." While many suggestions have been made on the
previous pages, recognize that not all risks/solutions apply to all
organizations: you have to make some judgement calls based on your
assessment of the risk. The judgement is based on how much loss you can
comfortably sustain, yet remain in business. The level of security
protection you require may not always be the same. It may vary with the
value of the hardware, software or data under consideration; the
security level, therefore, might be stated as "minimal," "discretionary,"
"mandatory," or "verified." The point is, as long as it's been
considered, you're closer to having a good security system than if you
have no policy or a policy that's based on guesswork.
You may find, after working on this for a while, that you may wish to
develop a separate policy for the selection or development, change,
testing and implementation of software. This might be stated as simply
as, "No system shall be acquired, developed, changed or implemented
without the prior approval of the Systems Steering Group." This might
also go on to cover documentation; e.g., "Documentation must be complete
for all systems prior to implementation, and must include sections on
files used, access controls, security considerations and controls
(etc.)."
Some further points for consideration are included in the next section.
- 26 -
11. COMPUTER SECURITY POLICY: POINTS FOR CONSIDERATION
Any policy on computer security must be based on the premise that
information is a valuable asset of the company, just like its premises,
equipment, raw materials, inventory and so on. More than one company has
gone under because they lost their accounts receivable data in a fire,
flood, or from a simple hard disk failure. The value of your data should
be subjected to a risk analysis, and all identifiable risks assessed. It
is not until you identify the risks that you can plan for a disaster
recovery.
Your policy might include some of the many things addressed previously in
this paper: e.g., storing data only on removable media (diskettes or
tapes), limiting access to bulletin boards, establishing password
controls, rules on physical security, use of immunization software, etc.
There are, however, some other specific points not previously discussed:
RESPONSIBILITY
Recognize that security is a management issue, not a technological
issue, and that setting policy is the responsibility of senior
management. They must be 'on board' and understand why a security policy
is needed to make it sensible and effective, and they must give overt
support.
Someone should be in charge of computer and network security. Without
someone in charge, important security tasks may not get done. The duties
of the security manager would include responsibility for limiting access
to the network, securing the information that passes over it, overseeing
password systems, and installing security packages that protect computers
from illegal tampering once a user is on the network. Other duties might
include analyzing the network for security weaknesses and helping users
understand the security strengths and weaknesses of the network.
The amount of time required of the system security specialist may depend
on the size of the organization, and on the number and complexity of the
systems in use or planned.
Having one person in charge is probably the ideal security arrangement.
The security specialist can become aware of all of the issues affecting
computer/network security, can schedule and establish priority for
actions, and can ensure that the actions are taken.
This position in the organization requires some authority and autonomy.
For instance, security is compromised if the boss shares his/her
password. The security specialist needs to be able to change the boss's
password if this happens, and gently but firmly discuss the problems
which could result.
In many organizations, putting two or more people in charge of something
diffuses responsibility. Each can think that some security concern was
the responsibility of the other. If two individuals are charged with
network security, be certain that they work well together, communicate
- 27 -
well, and will each put in their fair share of the analysis and work that
is required for security.
In some organizations, a "communications manager" is responsible for
limiting access to the network (with dialback modems and encryption
devices), while the network manager maintains password systems and
installs security software.
If someone is in charge of network security and you don't know about it,
then they haven't been very obvious about it. They need not be. But if
it is evident to you that security is lacking, then perhaps the issue of
responsibility should be examined (or re-examined).
BACKUPS
Those who are most zealous about backups are those who've been affected
in the past by a loss of data. If backups are performed every day, your
computer or network is probably in good shape when the hard disk or file
server goes to heaven. You will want to verify that this is the case,
since most organizations (and individuals) put this off... and off...
until it's too late.
Backing a system up once a week is not enough, unless the system is
rarely used. If your last backup was a week ago, and your hard disk or
the hard disk in the file server crashes, all users of the network have
lost one week's work.
This cost is enormous. If you have 10 users who have lost 30 hours of
work each, if each user is paid $20/hour, and overhead is 100%, then you
have just lost 10 x 30 x 20 x 2 = $12,000. If you assume that backup
takes one $20 hour with a tape drive, you could back the system up 600
times for $12,000. That's nearly three years, if backups are done five
times a week. Many hard disks will not run continuously for three years.
Even if you're a 'stand alone' computer user, your time is valuable. You
might consider a policy that, if recovery covers a period of more than
'x' days, it must be done on the employee's own time, and all deadlines
must be met - tough, but it get's the point across!
Irregular backups are a sign that backup is not taken as seriously as it
should be. It is probably wisest to do the arithmetic, comparing the
costs of backup with the costs of losing work for multiple users. The
cost comparison in the commentary on the second answer doesn't even
consider the possibility of losing irreplaceable files, such as those
containing new accounts receivable entries or new prospects.
Since file backup is a "private" activity, not knowing how often it
occurs does not mean that it does not occur. But if you have a security
concern, you should find out what the correct answer is. After all, if
you use the network, and it is not backed up frequently, it is your work
that is lost when the hard disk in the server crashes.
- 28 -
BEWARE: backing up is NOT enough! You MUST periodically run your
recovery procedure .... how else will you know it will work when you need
it most?
PURCHASING
The policy should state the controls in place for purchase of both
hardware and software, and it should be consistent and centralized.
Unless you've seen what some software can do to destroy security, or how
difficult it is to interconnect different equipment, this might seem to
destroy some autonomous activities in your organization. Autonomy be
darned, it's the company that's paying the bill.
MAINTENANCE AGREEMENTS
All warranty registrations must be mailed to the manufacturer, and
records kept of purchase dates, expiry dates and repairs made under the
warranty. Keeping accurate records has substantiated the complete
replacement of more than one machine.
SOFTWARE LOADING
The checking, copying and loading of software should be the
responsibility of one person or department. The 'penalty' for loading
illegal/unauthorized software can range from a note in the personnel file
to dismissal, depending on the organization. The opposite, copying the
organization's software for loading in another location, should also be
covered in the policy, because the company (as the registered owner)
could be party to a lawsuit without the ability to plead ignorance.
EMPLOYMENT TERMINATION
In several organizations, when a person submits their resignation, their
access to the computer system is immediately withdrawn. This, of course,
requires a close liaison with the personnel department in large
organizations. Many of these companies feel it's worth the salary cost
to have the person leave the premises immediately (escorted), and simply
pay out their notice period. If your company adopts such a policy, it
should be made very clear that it is not an indication of trust in the
person, but simply a means to reduce risk to the valuable resources of
hardware, software and data. It must be administered consistently and
equitably to avoid problems. There are problems with such a policy,
not the least of which could be someone who gives a very lengthy notice
period simply because they're aware of the policy - but you could
transfer them to a clerical job for the interim (like the mail room) or
to maintenance staff (washroom detail).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- 29 -
12. TO RUN SCAN (Virus detection software included on this diskette)
SCAN looks for 42 viruses in software files, but not in data files. I
know it works on Jerusalem-B because I used SCAN to detect that virus on
a machine at work. This is NOT the latest version of SCAN, but then
again, you're not likely to have the latest viruses (I hope).
If you want to print the documentation, type: COPY A:SCAN.DOC PRN
If you want to run SCAN, just type: A:SCAN [drive identifier]
e.g., A:SCAN C:
An article from the Washington Post, January 14, 1990, on Computer
Viruses was added to the diskette after this paper was written.
ref : google.com & yang bersangkutan...
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