Security Guideance

Aaron L. Meehan aaron at
Wed Feb 24 18:04:02 UTC 2010

On Tue, Feb 23, 2010 at 02:55:40PM -0600, Chris Adams wrote:
> Once upon a time, Matt Sprague <msprague at> said:
> > The user could also be running the command inline somehow or deleting
> > the file when they log off.   Check who was logged onto the server at
> > the time of the attack to narrow down your search.  I like the split
> > the users idea, though it could be several iterations to narrow down
> > the culprit. 
> We've also seen this with spammers.  They'll upload a PHP via a
> compromised account, connect to it via HTTP, and then delete it from the
> filesystem.  The PHP continues to run, Apache doesn't log anything
> (because it only logs at the end of a request), and the admin is left
> scratching his head to figure out where the problem is.
I've never used it myself, but Apache's mod_log_forensic is documented
to write two log entries for each request, one before and one after.


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