ClamAV Multiple Rem0te Buffer Overflows
Date
July 25, 2005
Vulnerability
ClamAV is the most widely used GPL antivirus library today. It provides file
format support for virus analysis. During analysis ClamAV Antivirus Library is
vulnerable to buffer overflows allowing attackers complete control of the
system. These vulnerabilities can be exploited remotely without user
interaction or authentication through common protocols such as SMTP, SMB, HTTP,
FTP, etc.
Specifically, ClamAV is responsible for parsing multiple file formats. At least
4 of its file format processors contain remote security bugs. Specifically,
during the processing of TNEF, CHM, & FSG formats an attacker is able to
trigger several integer overflows that allow attackers to overwrite heap data
to obtain complete control of the system. These vulnerabilities can be reached
by default and triggered without user interaction by sending an e-mail
containing crafted data.
Impact
Successful exploitation of ClamAV protected systems allows attackers
unauthorized control of data and related privileges. It also provides leverage
for further network compromise. ClamAV implementations are likely vulnerable in
their default configuration.
Affected Products
ClamAV – 0.86.1 (current) and prior
There are numerous implementations of ClamAV listed on their site which are
likely vulnerable. One party of note is Apple. Apple includes ClamAV by default
in Mac OS X Server. In addition, ClamAV has been ported to windows and a
variety of other platforms by third parties who’s implementations are also
likely vulnerable. Refer to vendor for specifics.
Credit
These vulnerabilities were discovered and researched by Neel Mehta & Alex
Wheeler.
Contact
security@xxxxxxxxxx
Details
http://www.rem0te.com/public/images/clamav.pdf