Here is an alert sent to the NTBugTraq list. I've got snort running on my boxen at home and it has been screaming since 8:00 this morning. I am already having trouble connecting to the boxes at home due to all the traffic. Dave Royer -----Original Message----- From: Russ [mailto:Russ.Cooper at RC.ON.CA] Sent: Tuesday, September 18, 2001 10:21 AM To: NTBUGTRAQ at LISTSERV.NTBUGTRAQ.COM Subject: Alert: Some sort of IIS worm seems to be propagating -----BEGIN PGP SIGNED MESSAGE----- There have been numerous reports of IIS attacks being generated by machines over a broad range of IP addresses. These "infected" machines are using a wide variety of attacks which attempt to exploit already known and patched vulnerabilities against IIS. It appears that the attacks can come both from email and from the network. A new worm, being called w32.nimda.amm, is being sent around. The attachment is called README.EXE and comes as a MIME-type of "audio/x-wav" together with some html parts. There appears to be no text in this message when it is displayed by Outlook when in Auto-Preview mode (always a good indication there's something not quite right with an email.) The network attacks against IIS boxes are a wide variety of attacks. Amongst them appear to be several attacks that assume the machine is compromised by Code Red II (looking for ROOT.EXE in the /scripts and /msadc directory, as well as an attempt to use the /c and /d virtual roots to get to CMD.EXE). Further, it attempts to exploit numerous other known IIS vulnerabilities. One thing to note is the attempt to execute TFTP.EXE to download a file called ADMIN.DLL from (presumably) some previously compromised box. Anyone who discovers a compromised machine (a machine with ADMIN.DLL in the /scripts directory), please forward me a copy of that .dll ASAP. Also, look for TFTP traffic (UDP69). As a safeguard, consider doing the following; edit %systemroot/system32/drivers/etc/services. change the line; tftp 69/udp to; tftp 0/udp thereby disabling the TFTP client. W2K has TFTP.EXE protected by Windows File Protection so can't be removed. More information as it arises. Cheers, Russ - Surgeon General of TruSecure Corporation/NTBugtraq Editor -----BEGIN PGP SIGNATURE----- Version: PGP Personal Privacy 6.5.2 iQCVAwUBO6dmcRBh2Kw/l7p5AQHJCgQA1JHwqF5RjJX+QVMMDUChVqn6yReQXqEH Tm8Ujms5+6ia0tcT1qmZWJV48eHYNzV3+AyyO6Gn8ds/NVYJUupDHB1Yy1DY/po6 iycY2qnARDJP6KNmHI0bAdBUBtsnVo5P9itElIoqKbAorQjamKI2eqd4TdE0yfIO hSW7yN2lhJc= =YAwc -----END PGP SIGNATURE-----