Only tested on... Mcafee VirusScan professional (8.0.0.12) Norton Antivirus 2003 Ad-Aware (6.0.1.181) The Cleaner
This is what i did, I craeated a account named "dumb_user" and log on to the account. I created a folder and copied a sample virus to the folder. Then i took the ownership of the folder and set the permission as, "I only can access" the folder and its content. eg: cacls.exe hUNT.exe /T /C /P dumb_user:R Then I switched back to "Administrative account" and tried doing "manual scan" for virus with mcafee and later norton in seperate machines. The manual scan was unable to pick the virus!!! But ya... if you try the same thing with a file and try executing the file the auto-protect engine will stop the virus from executing. So this is ONLY ISSUE FOR MANUAL SCAN ON ANTIVIRUS PRODUCTS. It seems like, in manual scan... the scanner runs under the security content of Administrator who is responsible for scanning the system........... hence the virus goes unnoticed due to NTFS file permission restriction. But, seems like... the Auto-Protect engine loads as a kernel driver so the virus gets stopped in the way during execution. *But ya... many trojan, spyware scanner i know just run with the Administrative privilage, so its a ISSUE for all those products. Please follow the procidure & confirm if other antivirus products are vulnerable as well. http://www.geocities.com/visitbipin/all.html thank you for your time, bipin gautam --- bipin gautam <[EMAIL PROTECTED]> wrote: > > --- 3APA3A <[EMAIL PROTECTED]> wrote: > > > Dear bipin gautam, > > > > Your statements about "all antivirus" and "design > > fault" are wrong, it's > > strongly depend on the way manual scanning is > > implemented in specific > > product. > > > > 1. many antiviral products implement their own > > kernel driver to access > > scanned file. For this case permissions have no > > impact for scanning. > > > > hello 3APA3A, > > Ok ya... i already mentioned the fact, If the > scanner > is unable to drop the privilege and run under the > security content of "dumb_user" the malicious code > goes undetected. Correct me if i am wrong, but.... > mostly (full-)system "manual scan" is executed as a > administrative job......... and i've already > mentioned > the fact, its MORE* a NTFS file permission problem. > > http://www.geocities.com/visitbipin/all.html > > IF A FILE PERMISSION IS SET IN A WAY... only THE > OWNER > OF THE FILE HAS ACCESS TO THAT FILE, Even softwares > running with ADMINISTRATIVE or SYSTEM privilage > don't > have access to the file, normally!!!!!!!!! Really > strange, cauz root should have atlest read access to > any file in the system regardless of the permission. > > Atlest, most trojan, spyware scanner gets executed > as > a admin. or system process. Regarding your > statement, > > >antiviral products implement their own > > kernel driver to access > > scanned file. > > I tested on norton av 2003 and few spyware product > "the cleaner" "Ad-aware" and by this way....... a > trojan bypassed the protection. > > Guys, please confirm this issue then.... i ain't in > a > research lab, just using my home PC. i'll test the > issue with mcafee and be back with the results > > > You still can bypass antiviral protection for > > manual scans with file > > encryption (on-access scanners may impersonate > > accessing user). This > > time file can only be scanned by > administrator > > if administrator is > > recovery agent. > > > > wow, i didn't thought of this..... > > bipin > > > > _______________________________ > Do you Yahoo!? > Declare Yourself - Register online to vote today! > http://vote.yahoo.com > > _______________________________________________ > Full-Disclosure - We believe in it. > Charter: > http://lists.netsys.com/full-disclosure-charter.html > __________________________________ Do you Yahoo!? Yahoo! Mail Address AutoComplete - You start. We finish. http://promotions.yahoo.com/new_mail _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
