Norton AntiVirus - Denial of Service









Norton AntiVirus Denial Of Service Vulnerability

*vulnerable [...only tested on!]

Symantec Norton AntiVirus 2003 Professional Edition
Symantec Norton AntiVirus 2002

*not vulnerable
Mcafee 7*
Mcafee 8*

Risk Impact: Medium
Remote: yes

While having a virus scan [automatic/manual] of some specially crafted compressed files; NAV triggers a DoS using 100% CPU for a very long time. Morover, NAV is unable to stop the scan in middle, even if the user wishes to manually stop the virus scan. 

Then, in this situation the only alternate is to kill the process. 

--- [Proof of Concept] ---
Please download this file. ( <--- For symantec. 

The file contains, 'EICAR Test String' burried in 49647 directories. This is just a RAW 'proof of concept'. A few 100kb's of compressed file could be crafted in a way... NAV will take hours or MIGHT even days to complete the scan causing 100% cup use in email gateways for hours. The compressed archive must not necessarily be a '.zip' to trigger this attack.

PLEASE: ...test this issue with other AV / trojan scanners as they might also be vulnerable. 

Bipin Gautam

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. 

# [2004-07-12]