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- Virus Simulator and Supplements
- Safe & Sterile
- Viruses Validate Security Measures
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-
- Virus Simulator and Virus Simulator Supplements
- Copyright Rosenthal Engineering 1991, 1993. All rights reserved.
- P.O.Box 1650 San Luis Obispo, CA USA 93406
-
-
- The time to be concerned about computer viruses is before you get one.
- Virus Simulator and Supplements are intended to help users and technical
- managers understand the problems viruses pose and provide a practical
- way to exercise the protective measures they have taken to defend their
- computer systems.
-
- These Virus Simulator programs generate safe and sterile, controlled
- test suites of sample virus programs. Virus Simulator's ability to
- harmlessly compile and infect with safe viruses, is valuable for
- demonstrating and evaluating anti-virus security measures without harm
- or contamination of the system. The infected programs can be used as
- bait for virus detecting programs to gain practical virus protection
- experience.
-
- Real Viruses or Simulated Viruses for Testing
-
- These test virus simulations are not intended to replace the
- comprehensive collection of real virus samples as maintained by
- Rosenthal Engineering and other anti-virus product developers for
- testing. They are, however, suitable for use by general end users,
- system administrators and educators. These virus simulations set off
- virus detectors for testing and demonstration without the danger
- associated with their malicious virus counterparts.
-
- The simulators all produce safe and controlled dummy test virus samples
- that enable users to verify that they have installed and are using their
- virus detecting programs correctly, additionally affording an
- opportunity for a practice training exercise under safe and controlled
- conditions.
-
- - - - - - - - - - - -
-
- Access to the Rosenthal Engineering Virus Collection
-
- The Virus Simulators and supplements are really intended to give users
- some hands on practical experience using their virus protection
- products, on their own systems, without using live ammo. The simulators
- ability to actually test products exhaustively is limited. That's why
- Rosenthal Engineering maintains a very comprehensive collection of real
- sample viruses for testing at our facility.
-
- Most users find these simulated viruses more than adequate for their
- needs, however anyone requiring access to our independent virus sample
- collection should contact us directly. The collection is generally
- recognized as one of the most comprehensive, verifiable available
- anywhere. It is accessible, in our facility, on a workstation dedicated
- for testing with real viruses.
-
- - - - - - - - - - - -
-
- Obtaining a Trusted Virus Simulator Copy
-
- Because of the security nature of this program, you should not trust it
- to be harmless unless you can directly trace its source to Rosenthal
- Engineering without compromise. Never make copies from anything other
- than the original write protected distribution disk. Remove all test
- viruses from your system immediately after completing tests. Insist on
- having the Virus Simulators generate your own unique simulation files
- and never accept or distribute the simulated viruses themselves. This is
- especially important if the simulations are to retain their safe and
- sterile integrity.
-
- There are several programs that generate the sample test viruses. Virus
- Simulator and the Virus Simulator Supplements. Virus Simulator is
- distributed as shareware. If you find the program useful, you are
- requested send in the $25 (US) single user registration fee. When the
- registration fee is received, the latest version of Virus Simulator
- along with all the Virus Simulator Supplements is sent by priority first
- class mail. Business, corporations, government agencies and institutions
- require a negotiated site license. The Virus Simulator Supplements are
- only available to registered users of Virus Simulator; The supplements
- are not shareware.
-
- - - - - - - - - - - -
-
- Virus Simulator
-
- Virus Simulator creates a simulated test suite of .COM and .EXE programs
- as well as boot sector and memory resident viruses. These programs
- contain the signatures (only) from real viruses. The programs themselves
- are not really infected with anything, but contain carefully selected
- portions of code from their real virus counterparts. Whenever possible,
- these sections of code or virus signatures are selected to trigger
- vigilant virus detectors. Since these are really only dummy viruses, not
- all infected program simulations produced by Virus Simulator will
- trigger every virus detecting program.
-
- In addition to simulating .COM and .EXE infected files, Virus Simulator
- allows the user to experiment with boot sector and memory resident virus
- simulations. Again, signatures (only) from real viruses are used, but
- the boot sector of the floppy disk is actually overwritten with
- executable code (you can verify this by resetting the system with the
- test floppy disk in place). The memory resident virus simulation
- actually puts a suspicious program in memory.
-
- Most often, real viruses are not created from scratch, but by modifying
- existing viruses and thus pose additional problems for virus detecting
- programs. To further emulate real viruses that might actually be
- encountered, Virus Simulator creates a completely new modified simulated
- virus the same way. No two files or disks will be created identically.
-
- Virus Simulator prompts the user to generate any (or all) of three test
- suite types: files, boot sector and memory.
-
- 1) Generate A:\VIRUS\VIR_#.COM & .EXE files. (Erase to remove)
- 2) Overwrite A: boot with (new) simulated virus (Format A: to remove)
- 3) Install memory test simulated virus (Power off system to remove)
-
- Any or all of the options may be selected at the same time.
-
- Place a freshly formatted diskette to be infected in the A: drive. If
- you select the "1) Overwrite A: boot sector" option, the the system will
- not be bootable from this disk, but will display an "Infected with
- simulated boot sector virus" message. Virus Simulator actually
- overwrites the boot sector with executable code; programs that report to
- intervene in this situation should report that.
-
- The A:\VIRUS\VIR_#.COM or .EXE files can be renamed and copied to other
- disks for testing but remember to erase all test viruses after
- completing your tests.
-
- If option three ( "3) Install memory test virus" ) is selected, a
- warning message will appear in the upper right corner of the screen
- until power for the system is turned off. When power is restored, the
- system will return to normal, and the memory virus will be removed.
- Virus Simulator actually places a suspicious test program in memory as a
- simulation and, programs that are report to intervene in this situation
- should report the memory resident program.
-
- How to Use Virus Simulator
-
- Copy your special write protected distribution disk to your working
- drive and store the original in a safe place.
-
- Run VIRSIM at the DOS prompt, and follow the directions displayed. Then
- use your anti-virus program to scan for viruses following the directions
- supplied with that product. A note here about false alarms especially
- when using disk caching. Anytime you read or write using a disk, the
- data is first buffered by memory. If you've just written or read a test
- suite, your virus scanning program may discover it still in the disk
- buffer memory. Just power down the system and watch it go away.
-
- These test suites are only safe and sterile simulations to evaluate your
- security measures. A virus detecting program is validated when it
- reports the simulations. Virus detecting programs that fail to find
- these simulations may indeed discover their real counterparts and
- variations, but should only be trusted after that ability is
- demonstrated.
-
- Virus Simulator and Virus Simulator Supplements will only generate file
- and boot sector simulations on a formatted disk in drive A:, you must
- have an A: drive. Copy VIRSIM.COM (and for registered users only,
- VSIM_MTE.COM, VSIM_B.COM and VSIM_C.COM) to whatever drive you wish to
- run it from. Precautions have been taken to force VIRSIM to run only
- from the default directory.
-
- NOTE. A:> VIRSIM or C:> VIRSIM (works ok)
-
- C:> A:VIRSIM or C:>\TEST\VIRSIM (won't work)
-
- VIRSIM.COM (and the supplements) compiles simulated viruses directly and
- when scanned by virus detection programs, must always indicate being
- free of infection. Only the simulated viruses should report any
- infection. Each time Virus Simulator is run, it generates a completely
- new and unique suite of with accompanying documentation. Text files
- A:VIR_LIST.DOC and A:VIR_BOOT.DOC are created at execution time and
- describe each unique virus test simulation suite. Executing the
- generated test suite programs is not required. If executed, they will
- only display their Rosenthal Engineering origin.
-
- - - - - - - - - - - -
-
- Virus Simulator Supplement B
-
- Once the user has gained experience using the original Virus Simulator,
- the supplements offer additional insights into how viruses work, and
- more importantly, how to defend against them.
-
- The Virus Simulator B Supplement provides users with hands on experience
- protecting themselves from a boot sector virus. Although easily
- detected, these are by far the most prolific and extremely infectious.
- Like the other simulations the test samples are completely safe, but are
- far more operational, and provide users with the hands on experience
- required to defend themselves.
-
- Several educational institutions have now incorporated this
- demonstration into their lesson plans. It harmlessly illustrates the
- importance of adhering to established anti-virus security measures quite
- dramatically.
-
- This type of virus hides in a special portion of the disk reserved for
- the power up sequence, called "booting" and is therefore called the
- "boot track" or "boot sector". A boot sector virus replaces the
- legitimate boot sector program with its' own code. When the user "boots"
- from the infected disk, the virus first loads itself into the computer
- ahead of the legitimate programs.
-
- Using Virus Simulator Supplement B (registered users only)
-
- Copy VSIM_B.COM from the special write protected distribution disk to
- your working or hard disk. Use a freshly formatted disk in drive A. You
- must have an A: drive.
-
- Run the VSIM_B from the DOS prompt and the program will instruct the
- user to select the anti-virus product they employ. These are listed
- alphabetically.
- The Virus Simulator B Supplement program infects the floppy disk and
- makes a DOC file labeling the disk as well. Users are encouraged to also
- mark the disk label appropriately as well. Be sure to plainly mark the
- sample disk so you don't stumble across it by accident and panic at some
- future date. As a convenience, the simulation will expire in a few days
- on systems that support a CMOS clock.
-
- You can now scan the disk etc. as the anti-virus product recommends.
-
- Now the fun part.... With the disk in place, re-boot the system.
- The boot program displays it's intention (Test Virus), the copyright,
- the expiration date and loads itself into memory. The system then boots
- through from the hard drive, while "TEST VIRUS in memory!" flashes in
- the upper right corner of the screen and the speaker beeps about every
- seven seconds. Other than the beeping and flashing, the system appears
- to work normally. If you are using MS Windows, the beeping will continue
- even though the display remaps. If you open a DOS window, from within MS
- Windows, the flashing message will display as well.
-
- You now have about four minutes to try your anti-virus measures, or what
- ever. Then, the screen becomes dominated with the "TEST VIRUS" flashing
- message. The beep rate goes up to about two seconds, and on most
- systems, the keyboard locks up! If you are in MS Windows, the mouse if
- left enabled so you can exit elegantly, the keyboard is then re-enabled
- when you return to DOS for a few minutes and finally locks again.
-
- Some BIOS's allow you to disable booting from the A drive, which
- prevents the demonstration from working. Real viruses have no problem
- infecting your hard drives' boot sector, but these simulations are safe
- so they will only boot from the floppy in A:, they will not infect or
- otherwise compromise a hard drive or other disks. Unlike these safe and
- sterile simulations, real viruses are not limited to being harmless.
-
- - - - - - - - - - - -
-
- Virus Simulator MtE Supplement
-
- Viruses are becoming much more sophisticated and difficult to combat
- especially with the introduction of polymorphic mutating viruses such as
- those based on the Dark Avenger MtE Mutation engine. These viruses
- obsolete the traditional pattern matching techniques of detection, which
- are ineffective against this type of virus.
-
- VSIM_MTE.COM compiles a safe set of test viruses and special dummy
- program files they will infect (only). The test viruses will only infect
- the special dummy test programs generated by the Virus Simulator MtE
- Supplement. Unlike their malicious real world counterparts, these
- simulations will only attack the dummy files provided in the A:\M_VIRUS
- directory. Provisions have been taken to discourage modification and
- tampering. Both .EXE and .COM viruses and dummies are provided. With the
- exception of their special safety and security provisions, the MtE test
- simulations are real polymorphic viruses.
-
- At the heart of these MtE virus simulations is an actual MtE mutation
- engine. The MtE engine provides virus writers with the ability to turn
- their relatively simple programs into very sophisticated polymorphic
- viruses which are extremely difficult to detect by virus scanners. Each
- time the virus infects a host program, it mutates, changing its
- signature pattern to avoid recognition. A few examples of viruses that
- employ the MtE engine are:
-
- Dark Avenger Mutating Engine, Dame, MtE, Pogue, Gotcha, 7S, Mut,
- Dedicated, Fear, Groove, Coffee Shop, MtE-Spawn, Questo, Crypto Lab,
- Encroach.
-
- Although the MtE simulations produced by this program are safe and
- controlled, they are real viruses, capable of infecting their special
- dummy host programs. Vigilant anti-virus programs that are capable of
- reliably detecting the MtE mutation engine should report these
- simulations as being infected. Because these are polymorphic viruses
- several samples are required to validate a virus detector, as each time
- the virus mutates in attempt to avoid detection, its signature changes.
-
- Using the MtE Supplement Virus Simulations
- (registered users only)
-
- To generate the MtE simulations and dummy files to be infected, run
- VSIM_MTE from the default directory. Once again, make sure you have
- installed your anti-virus software in accordance with the author's
- instructions. Prepare freshly formatted disks to be infected in your A:
- drive.
-
- When you run the MtE supplement, it will first verify itself (by voice)
- and display the sign on message, which asks if you wish to continue.
- Enter "Y". (NOTE! These programs should be run directly from the DOS
- prompt and not from inside MS Windows)
-
- The Virus Simulator will then generate a directory full of dummy test
- programs, until the disk is nearly full (allowing for an increase in
- size as the programs are infected). Originally, only the first two
- samples (A:\M_VIRUS\VIR_1.EXE and A:\M_VIRUS\VIR_2.COM) will be
- infected. Examine the directory, and you will see a considerable
- difference in size between the infected and clean programs. Execute an
- infected program, and you can observe that the test virus will spread to
- the other samples (only). The infected programs will display that they
- are indeed infected and ask if you wish to continue. If you enter "Y",
- the simulation will spread to from one to 15 other programs. Those
- programs can then be run and they will, in turn infect the others. If
- you enter "A" (for all) instead of "Y", the infection will spread to all
- the dummy .COM or .EXE samples in the directory. Because of the
- sensitive nature of these test samples, the infection will not spread to
- any sample which has been modified. For security reasons the infections
- will only activate on the A: drive in the A:\M_VIRUS directory, and only
- if no modifications have been made to the dummy program files.
-
- Once the files produced by Virus Simulator MtE Supplement become
- infected, your virus detecting program should report them as such.
-
- - - - - - - - - - - -
-
- Virus Simulator Supplement C
-
- The Virus Simulator Supplement C illustrated how a companion virus
- works, and provides a functional demonstration that affords an
- opportunity to exercise protective measures. These simulations, like the
- others, are dramatic, but safe and harmless.
-
- Companion viruses exploit a feature of the computers' operating system
- that differentiates between programs with a COM or EXE file extension in
- their name. When two programs have the same file name, for example
- VIRUS_1.COM and VIRUS_1.EXE, the operating system will attempt to run
- the COM program first.
-
- The companion virus assumes the name (with a COM extension) of a
- legitimate program with an EXE file name extension. When the user enters
- the name of the program, the companion virus does its dirty work first,
- and then allows the legitimate program to operate normally. Usually the
- whole procedure is completely transparent to the user to avoid detection.
-
- If the user examines the original program, they find it unchanged. The
- companion virus remains even if the user reloads the legitimate program
- directly from the distribution backup unless the program with the same
- name (and COM file extension) is removed.
-
- Using the Virus Simulator Supplement C
- (registered users only)
-
- Copy VSIM_C.COM from the special write protected distribution disk to
- your working or hard disk. As with the other simulators, place a freshly
- formatted disk in drive A.
-
- When you run VSIM_C it will generate several dummy programs on the
- floppy disk in the A:\C_VIRUS directory. These test programs are
- identical except for their name (VIRUS_##.EXE). One of them is
- associated with a companion virus simulation.
-
- When the VIRUS_## programs are run, they will only display a simple
- message. However, when the program associated with the companion virus
- simulation runs, it will produce a dramatic, but harmless demonstration.
-
- Execute each of the test programs until you discover the companion
- virus. To terminate the demonstration, simply reset the system. You may
- repeat the demonstration without generating new dummy samples on the
- floppy disk again. You'll notice the simulation will assume the name of
- a different dummy test program each time.
-
- To reveal the companion virus simulation use the DOS command ATTRIB
- A:\C_VIRUS\*.* and you will discover the hidden companion virus
- simulation.
-
- With DOS 5 and above, you can also use the DOS command DIR A: /S /A
-
- - - - - - - - - - - -
-
-
- How Anti-Virus Measures Protect Your System
-
- There are several popular methods employed to detect viruses that these
- simulators can exercise. Generally they occupy three categories;
- scanners, monitor filters, and change monitors.
-
- Scanners are the most popular. They check the system for pieces of code
- that form a signature or fingerprint that is unique to each virus.
- Because the scanning program will only detect viruses that it knows the
- signature for, it may not detect a new or modified virus. Virus
- Simulator offers the signatures of many real viruses, but may not be
- using the same signatures your viruses detector uses. If your signature
- scanner fails to report the dummy sample test viruses produced by Virus
- Simulator, it is most likely that they are different than those required
- by that scanner. Unlike the test viruses produced by the MtE Supplement,
- the Virus Simulator and other supplements produce only dummy viruses,
- not real viruses.
-
- Monitor filters are TSRs (terminate and stay resident programs) that
- watch for suspicious virus-like activity, such as creating or writing to
- a program file or the boot sector or terminating with a TSR still active
- in memory. Virus Simulator should have no difficulty demonstrating this
- type of virus detector as it allows the user to actually overwrite the
- boot sector of the floppy disk, install a very suspicious (but safe) TSR
- in memory, and generate plenty of executable program files.
-
- Change monitors learn what the original program or boot sector etc.
- looks like and re-examines them periodically for modification. Virus
- Simulator and supplements can demonstrate this, since the user can
- actually elect to modify the floppy disk boot sector. Additionally, when
- the MtE dummy test programs become infected, they change substantially.
-
- You may also conduct additional tests on your system. For example, many
- users mistakenly believe that changing the attribute of a program to
- READ-ONLY will protect it from infection. You can test this using the
- DOS ATTRIB command for example ( C>ATTRIB +R A:\M_VIRUS\VIR_99.EXE )
- will not protect the dummy files from becoming infected by the MtE
- simulation.
-
- The best and simplest way to protect a floppy disk from infection is to
- take advantage of the write protect tab. These are very effective unless
- yours is some how inoperative. You may wish to conduct your own test by
- enabling the write protect tab, and repeating the experiment. If your
- write protect circuitry is functional, you should not be able to make
- modifications to the protected disk and the MtE simulations will be
- unable to infect the dummy files.
-
- - - - - - - - - - - -
-
-
- History of Virus Simulator
-
- Virus simulator was first developed to support testing my System Monitor
- program. System Monitor was not a virus scanner or even a program
- devoted to exclusively to virus protection. There are enough things that
- go astray in a normal computing environment to justify System Monitor on
- its own. It installs in your IBM PC/XT/AT 386 or 486 Compatible computer
- to test and extensively monitor a number of performance indicators. Each
- time you use your computer, System Monitor re-evaluates the system and
- alerts you to any discrepancies it finds with an announcement that is
- hard to ignore.
-
- You install System Monitor as soon as you're confident that your
- computer is configured and operational. From then on, System Monitor
- will intervene immediately upon detecting problems, usually long before
- a user even suspects any difficulty. This early monitoring and detection
- is essential in avoiding and correcting problems before they can
- compound. It also provides formidable anti-virus protection.
-
- Virus Simulator can help determine which anti-virus programs are best
- for you. These programs can then be installed ahead of System Monitor so
- a virus that attempts to disable either of these programs will have the
- very Herculean task of disabling or circumventing them both, or risk
- detection by the other.
-
- The first version of Virus Simulator was only intended as a tool to
- assist volunteers who were beta testing System Monitor in a real world
- environment. Before beta testing, System Monitor had been tested in a
- controlled environment, using a considerable collection of real viruses.
- You can imagine the enthusiasm my beta testers showed to turning real
- viruses loose on their systems.
-
- During the beta testing of System Monitor, we discovered a real need for
- Virus Simulator beyond its original intention. Some virus detectors not
- only didn't find the simulated viruses, on closer inspection, they
- didn't find the real ones either. We found several cases where no
- security procedures were being adhered to and even though the
- organization had purchased site license for a very capable program. Few
- users had ever run it. Additionally, a virus detecting program thought
- to be protecting a system used to duplicate distribution disks for other
- offices, was found to be an obsolete version, which missed nearly all of
- the currently simulated viruses. No virus protection program will ever
- be effective without the cooperation of its users. Virus Simulator
- provides a means to verify adherence to established security procedures.
-
- Virus Simulator was made available to assist system administrators, end
- users, and educators enabling them to perform their own tests. Virus
- Simulator is not a replacement for the comprehensive collection of real
- viruses maintained by Rosenthal Engineering and other researchers for
- testing anti-virus programs.
-
- Viruses are a form of terrorism and require many of the same
- precautionary measures. Airports test the effectiveness of their
- security measures in much the same way. An official, disguised as a
- passenger, will attempt to bring a disarmed bomb through, trying to
- evade security measures and avoid detection. Real viruses, like real
- terrorists, are much more difficult to test with. The test viruses
- generated by these virus simulators are safe and controlled, but form a
- validation test suite that trigger vigilant anti-virus detectors.
-
- Not all virus detectors use the same virus signatures that Virus
- Simulator supplies. Some anti-virus software (like Dr. Solomons Tool
- Kit, TBSCAN, VShield, VirStop and others) provide their own dummy sample
- programs, so users can perform similar tests. Users can use these safe
- simulations to verify that their anti-virus measures are correctly in
- place and functional.
-
- Anti-virus programs that report suspicious activity (like FLUSHOT or
- SECURE ) should detect Virus Simulator actually overwriting the sample
- floppy disk boot sector, installing an unauthorized memory resident
- program, or modifying an executable program.
-
- Authors of viruses are very aware of how virus detectors work. As
- polymorphic viruses (especially the MtE mutation engine) were developed,
- signature scanning alone became inadequate. The Virus Simulator MtE
- Supplement addresses that need and some of the other comments users have
- brought to my attention.
-
- As more users of these programs began incorporating them into training
- lesson plans, and demonstrations, the additional supplements B and C
- were added.
-
- - - - - - - - - - - -
-
- Statistics, Probability and Making Sense of Tests
-
- Virus Simulator makes an infinite number of simulated test viruses by
- varying each one in a different way. This is much the same way a real
- virus might be discovered in the world at large. Even testing with a
- program infected with a real virus can not assure every combination will
- be examined: Is it a .COM file? .EXE? system? compressed? Is it the same
- for all programs or just large ones? How about files created before or
- after a certain date or time. What about a virus that was modified, even
- trivialy, offset a few bytes or changed from one message to another. Or,
- a virus that only attacks one vendor's brand of software. The only way
- to test with any kind of absolute certainty would be to perform tests
- with every combination and variation, and, even then, hope you didn't
- overlook any.
-
- Now, try that with well into many hundreds of viruses and combinations.
- It becomes apparent that no matter how exhaustive the tests are, they
- are just random, probabilistic distributions. The study of probability
- assumes that you know the entire population or universe from which you
- are going to sample. Statistics assumes that you have only a sample and
- that you are trying to determine, or at least guess, the parameters or
- characteristics of the most likely population or source from which the
- sample was taken. That's what Virus Simulator supplies, a large enough
- sample population size to establish statistical significance with some
- reliability.
-
- A large sample size is especially important when attempting to validate
- polymorphic viruses, as each sample will have a different signature.
- These sophisticated viruses attempt to avoid detection by altering their
- signatures, so it is not uncommon for several copies to escape
- detection. The Virus Simulator MtE Supplement attempts to generate as
- broad a spectrum of test samples as practical.
-
- Allowing Virus Simulator to fill a single 360 k disk should be more than
- adequate to support reliable testing. Although a 1.2 meg disk offers
- some improvement, additional disks offers diminishing benefits, as the
- distribution confidence interval shows an insignificant improvement
- beyond that point. In other words, for files... One disk ought to do it.
-
- Testing using boot sector viruses is another matter, because unlike the
- hundreds of files that can be created on a disk by Virus Simulator,
- there is only one boot sector per disk. You can generate a simulated
- boot sector virus onto as many different disks as you like or overwrite
- a single disk repeatedly. A new simulation will be generated each time.
-
- - - - - - - - - - - -
-
-
- Bibliography and Additional Sources of information
-
-
- National Computer Security Center - Guidelines for Formal Verification
- Systems (NCSC-TG-014)
-
- National Computer Security Center - Computer Security Subsystem
- Interpretation of the Trusted Computer System Evaluation Criteria
- (NSC-TG-009)
-
- National Computer Security Center - Rating Maintenance Phase
- Program Document (NCSC-TG-013)
-
- National Computer Security Center, Trusted Network Interpretation
- of the Trusted Computer System Evaluation Criteria (NCSC-TG-005)
-
- Department of Defense - Trusted Computer Systems Evaluation
- Criteria (DOD 5200.28-STD)
-
- Richard A. Kemmerer - Verification Assessment Study Final Report,
- University of California
-
- Peter J. Denning, ACM Press/Addison-Wesley - Computers Under
- Attack: Intruders, Worms and Viruses
-
- Lance J. Hoffman, Van Nostrand Reinhold, Anne Branscomb - Rogue
- Programs: Viruses, Worms and Trojan Horses
-
- Springer-Verlag, David Ferbrache - A Pathology of Computer Viruses
-
- Dr. Fred B. Cohen, ASP Press - A Short Course on Computer Viruses
-
- Dr. Solomons Virus Encyclopedia - S & S International
-
- R. Burger - Computer Viruses: A High-Tech Disease
-
- Dr. Mark Ludwig - The Little Black Book of Computer Viruses
-
- Virus Bulletin Ltd - Abingdon England
-
- Virus News International Ltd. - Berkhamsted, Hertfordshire UK
-
- Computer Virus Developments Quarterly - American Eagle Pub. Inc.
- P.O. Box 41401, Tucson, Arizona 85717
-
- - - - - - - - - - - -
-
-
- Shareware Announcement
-
-
- Please feel free to use and evaluate Virus Simulator without charge for
- 10 days. You are encouraged to copy and distribute self extracting
- archive VIRSIM2C.EXE freely, provided it remains unmodified, complete in
- it's original form, and no fee (other than a nominal copy charge) is
- required.
-
- The Virus Simulator Supplements are only available directly from
- Rosenthal Engineering once the single user registration fee is received.
- The supplements are not shareware. All copyrights are reserved.
-
- Once the required registration fee is received, the latest registered
- version of Virus Simulator along with all the Virus Simulator
- Supplements will be sent by priority first class mail.
-
- Software License Agreement
-
- This Software is copyrighted material. It is not sold, but licensed. The
- registration fee must be paid before evaluation period expires or use of
- the software must be discontinued.
-
- You are encouraged to copy and distribute only the Virus Simulator self
- extracting archive VIRSIM2C.EXE file freely, provided it remains
- unmodified, complete in it's original form and no fee (other than a
- nominal copy charge) is required. This software is provided "as is"
- without warranty, either expressed or implied.
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- You may not make any changes or modifications to the software and you
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- software.
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- This constitutes the entire agreement and understanding between the
- parties and supersedes any prior agreement or understanding whether oral
- or written and may only be modified in writing.
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- This software is provided "as is" without warranties of any kind.
- Responsibility rests entirely with the user to determine its fitness for
- a particular purpose. ROSENTHAL ENGINEERING SHALL NOT IN ANY CASE BE
- LIABLE FOR SPECIAL, INCIDENTAL, CONSEQUENTIAL, INDIRECT OR OTHER SIMILAR
- DAMAGES ARISING FROM ANY USE OF THIS SOFTWARE. Some states may not allow
- these limits on warranties, so they may not apply to you. In no case
- shall Rosenthal Engineering's liability exceed the license fees paid by
- you to Rosenthal Engineering for the right to use the Licensed Software.
-
- The single users license is obtained by sending your check for $25 (US)
- to:
-
- Rosenthal Engineering, P.O.Box 1650, San Luis Obispo,CA 93406 USA