Multiple AV Vendor Incorrect CRC32 Bypass Vulnerability.

[Bipin Gautam <visitbipin () hotmail com>]

Multiple AV Vendor Incorrect CRC32 Bypass Vulnerability. 

Affected Product:

AntiVir 6.30.0.5 
AVG 718 
Sybari (Antigen for M$ exchange) 7.5.1314
Symantec 8.0
McAfee 4442
BitDefender 7.0 
 

POC: http://www.geocities.com/visitbipin/happy-crc.zip

Description:
if you create a zip archive with invalid CRC checksum...... some AV skip the archive marking it as clean........ by 
this way, you can bypass antivirus gateways and slip in any attachment without scanning the archive. Moreover, these 
days.... software tools automatically repair a *broken* archive.

Useful Reference on zip header: http://www.pkware.com/company/standards/appnote/

regards,
Bipin Gautam
http://www.geocities.com/visitbipin/


Disclaimer: The information in the advisory is believed to be accurate at the time of printing based on currently 
available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no 
warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, 
indirect or consequential loss or damage arising from use of, or reliance on this information.