COMMAND
MAILsweeper
SYSTEMS AFFECTED
Content Technologies' MAILsweeper for SMTP
PROBLEM
Raj Wurttemberg discovered a DOS for Content Technologies'
MAILsweeper for SMTP product. He noticed that no mail was leaving
the MAILsweeper SMTP gateway so he checked the queues... He had
over 10,000 e-mails queued up! So he tried to stop the
MIMEsweeper service, it wouldn't stop. He set the MAILsweeper
service startup to manual and rebooted the machine. When the
computer came back up he copied off the offending message pair
and started it back up again. About 10 minutes later he saw that
both CPU's were maxed out and no more mail was flowing. He did
the same process as above but he noticed that the file was the
same length. He compared the two and discovered that although
they were slightly different e-mails they had the same
attachments.
At this point Raj called Content technologies and sent them a
compressed version of the DOS message via Linux box. As soon as
it hit *their* MAILsweeper 4.1.x server it promptly hung one of
the message processing threads.
The Zip file containing the message pair to hang MAILsweeper is
available at:
http://www.starbase-01.com/misc/lockmsw.zip
At this point ANY Content Technologies MAILsweeper for SMTP could
be taken out of service with the "lockmsw.zip" file above.
SOLUTION
Testing has shown that MAILsweeper for SMTP 4.1_6 / 4.1_7 / 4.1_9
processes this message without difficulty and quarantines it
because one of the message components is corrupt.