On Thu 06 Oct 2011 10:40:35 PM IST, Nilesh Govindarajan wrote: > On Thu 06 Oct 2011 10:32:14 PM IST, Michael Mol wrote: >> >> On Oct 6, 2011 12:57 PM, "Nilesh Govindarajan" <cont...@nileshgr.com >> <mailto:cont...@nileshgr.com>> wrote: >>> >>> On Thu 06 Oct 2011 09:06:06 PM IST, Alberto Luaces wrote: >>>> Nilesh Govindarajan writes: >>>> >>>>> One of the servers I manage has a strange problem. >>>>> >>>>> Every 24h, someone starts a process shows up as perl in the list, but >>>>> launching command is /usr/sbin/httpd. >>>>> It shows just one process, but when I run something like this: >>>>> >>>>> ps -C perl -o cmd,pid >>>>> >>>>> I get some 5-6 processes alternatively with cmd as /usr/sbin/httpd or >>>>> /usr/bin/perl. >>>>> >>>>> The even more interesting thing is, /usr/sbin/httpd does not exist. >>>>> I suspect a rootkit, but chkrootkit & rkhunter reported nothing. >>>>> >>>>> Also, I found a mysterious file: /tmp/ips.txt with following content: >>>>> xxx.xxx.xxx.xxx >>>>> 127.0.0.1 >>>>> addr:xxx.xxx.xxx.xxx >>>>> addr: >>>>> addr:127.0.0.1 >>>>> addr: >>>>> >>>>> Somebody is aware of a malware/rootkit which creates such files? >>>> >>>> I had some of that recently. The attacker used a instance of >> phpmyadmin >>>> to inject into its URL a wget command to download a perl script from >>>> another site. Look for `wget' into apache logs. >>>> >>> >>> @all >>> Apache was never installed & I don't see any reason to install it >>> because nginx satisfies my needs. I grepped for the string wget in all >>> logs and php files, found some, but they were for libssh2 in wordpress >>> code. >>> @Michael, >>> I thought of doing that, but before I discovered the file, I'd already >>> killed the processes. Will check later when the process is relaunched >>> sometime later. >> >> You might crank up service log levels in anticipation, too, and prod >> your firewall to log unusual-but-allowed connections, too. >> > > I just found something: > http://blog.vaultpress.com/2011/08/02/vulnerability-found-in-timthumb/ > Data on just one of the wordpress installations seems to be deleted, > which seems to me as an effect of this. We're removing timthumb and > will watch. Thanks for the tip :-) >
After about 72 hours of watch, it seems timthumb was the culprit. No attack/overload since 72h. -- Nilesh Govindarajan http://nileshgr.com
