Av issuesMar 12 2005 09:40AM Bipin Gautam (visitbipin hotmail com)
In-Reply-To: <20050311203150.17236.qmail (at) www.securityfocus (dot) com [email concealed]>
In Local file header if you modify "general purpose bit flag" 7th & 8'th byte of a zip archive with \x2f ie: "\" F-port, Kaspersky, Mcafee, Norman, Sybari, Symantec seem to skip the file marking it as clean!!! This was discovered during the analysis of "Multiple AV Vendor Incorrect CRC32 Bypass Vulnerability."
Quick/rough conclusion were drawn using www.virustotal.com
poc: http://www.geocities.com/visitbipin/gpbf.zip
Well, tested with F-prot, DrWeb, *Symantec 8.0 long ago... lately verified it using virustotal.com If you have a long archive coment... in a zip archive these AV can't detect virus embedded in it. I came to know Symantec 8.1 is immune to the bug?
In Local file header if you modify "general purpose bit flag" 7th & 8'th byte of a zip archive with \x2f ie: "\" F-port, Kaspersky, Mcafee, Norman, Sybari, Symantec seem to skip the file marking it as clean!!! This was discovered during the analysis of "Multiple AV Vendor Incorrect CRC32 Bypass Vulnerability."
Quick/rough conclusion were drawn using www.virustotal.com
poc: http://www.geocities.com/visitbipin/gpbf.zip
Well, tested with F-prot, DrWeb, *Symantec 8.0 long ago... lately verified it using virustotal.com If you have a long archive coment... in a zip archive these AV can't detect virus embedded in it. I came to know Symantec 8.1 is immune to the bug?
POC: http://www.geocities.com/visitbipin/long_coment.zip
regards,
bipin gautam
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