旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � VIRUS REPORT � � Lehigh � 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date of Origin: late 1987. Place of Origin: Lehigh University, Pennsylvania. Host Machine: PC compatibles. Host Files: Remains resident. Infects COMMAND.COM. Increase in Size of Infected Files: overwrites files. Nature of Damage: Corrupts program or overlay files. Overwrites the FAT and boot sector after infecting four floppies. Detected by: Scanv56+, F-Prot, IBM Scan, Pro-Scan. Removed by: CleanUp, or use MDisk and replace COMMAND.COM with a clean copy, or use F-Prot. Scan Code: 50 53 80 FC 4B 74 08 80 FC 4E 74 03 E9 77 01 8B DA 80 7F 01 3A 75 05 8A 07 EB 07. You can also search at offset 01CH for B4 19 CD 44 04 61 1E 51 52 57. History: This is a COMMAND.COM infector that first surfaced at Lehigh University in late 1987. It is one of the best known of viruses, and widely discussed and analyzed. Description of Operation: Infects only COMMAND.COM, where it overwrites the stack space. If a disk which contains an uninfected copy of COMMAND.COM is accessed, that copy is also infected. A count of infections is kept within each copy of the virus, and when this count reaches 4, every disk (including hard disks) currently in the computer is trashed by overwriting the initial tracks (boot sector & FAT). Infection changes the date and time of the infected file. If a floppy with an uninfected COMMAND.COM is write-protected, there will be a "WRITE PROTECT ERROR" message from DOS. I have reprinted below the warning that Kenneth van Wyk distributed on this virus. "WARNING: MS-DOS COMMAND.COM "virus" program will reformat your disks!! "Last week, some of our student consultants discovered a virus program that's been spreading rapidly throughout Lehigh University. I thought I'd take a few minutes and warn as many of you as possible about this program since it has the chance of spreading much farther than just our University. We have no idea where the virus started, but some users have told me that other universities have recently had similar problems. "The virus: the virus itself is contained within the stack space of COMMAND.COM. When a PC is booted from an infected disk, all a user need do to spread the virus is to access another disk via TYPE, COPY, DIR, etc. If the other disk contains COMMAND.COM, the virus code is copied to the other disk. Then, a counter is incremented on the parent. When this counter reaches a value of 4, any and every disk in the PC is erased thoroughly. The boot tracks are nulled, as are the FAT tables, etc. All Norton's horses couldn't put it back together again... :-) This affects both floppy and hard disks. Meanwhile, the four children that were created go on to tell four friends, and then they tell four friends, and so on, and so on. "Detection: while this virus appears to be very well written, the author did leave behind a couple footprints. First, the write date of the COMMAND.COM changes. Second, if there's a write protect tab on an uninfected disk, you will get a WRITE PROTECT ERROR... So, boot up from a suspected virus'd disk and access a write protected disk - if an error comes up, then you're sure. Note that the length of COMMAND.COM does not get altered. "I urge anyone who comes in contact with publicly accessible disks to periodically check their own disks. Also, exercise safe computing - always wear a write protect tab. "This is not a joke. A large percentage of our public site disks has been gonged by this virus in the last couple days." The Lehigh original virus has been sporadically reported at dozens of installations outside of the university for over a year. It is not a particulary successful replicator <197> probably because of the extremely short activation fuse - and it is difficult to detect and report because there are few symptoms prior to activation. But there should certainly be no surprise that it's in the public domain. John McAfee has written: "The belief that viruses can be contained by early counter-action is belied by the Lehigh University experience. I have spoken to a number of individuals at the University who belived that the virus had somehow been contained because "no copies of the virus were distributed to outside organizations". This assumed, of course, that the original virus writer gave up after being foiled at Lehigh and did not insert the virus at any other location, and that all copies of the virus at Lehigh had indeed been accounted for. The first issue rests solely in the hands of the perpetrator and is beyond any containment controls. The second issue relies on an error-free containment process - allowing no possibility for overlooking, losing or mistaking an infected diskette. In any case, the Lehigh virus was by no means contained. I received a copy, as did virtually every virus researcher, in mid-1988, and infection reports issued throughout the year from universities, corporations and individual computer users." �袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴� � This document was adapted from the book "Computer Viruses", � � which is copyright and distributed by the National Computer � � Security Association. It contains information compiled from � � many sources. To the best of our knowledge, all information � � presented here is accurate. � � � � Please send any updates or corrections to the NCSA, Suite 309, � � 4401-A Connecticut Ave NW, Washington, DC 20008. Or call our BBS � � and upload the information: (202) 364-1304. Or call us voice at � � (202) 364-8252. This version was produced May 22, 1990. � � � � The NCSA is a non-profit organization dedicated to improving � � computer security. Membership in the association is just $45 per � � year. Copies of the book "Computer Viruses", which provides � � detailed information on over 145 viruses, can be obtained from � � the NCSA. Member price: $44; non-member price: $55. � � � � The document is copyright (c) 1990 NCSA. � � � � This document may be distributed in any format, providing � � this message is not removed or altered. � 훤袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴暠  Downloaded From P-80 International Information Systems 304-744-2253