Home / malware Win32.Bagle.BD - BG @mm
First posted on 21 November 2011.
Source: BitDefenderAliases :
Win32.Bagle.BD - BG @mm is also known as Bagle.PAC, (kaspersky.
Explanation :
The files come packed with PeX, a popular PE file encryption utility.
PeX-compressed/encrypted files are fairly easy to decrypt / unpack, although PeX makes use of many tricks, like generating exception (after it has previously set up an exception handler), anti-disassembling macros (like jumping in the middle on an instruction) etc.
The Bagle trojan overwrites the hosts file with a 3783-byte buffer, that contains:
127.0.0.1 localhost
127.0.0.1 ad.doubleclick.net
127.0.0.1 ad.fastclick.net
127.0.0.1 ads.fastclick.net
127.0.0.1 ar.atwola.com
127.0.0.1 atdmt.com
127.0.0.1 avp.ch
127.0.0.1 avp.com
127.0.0.1 avp.ru
127.0.0.1 awaps.net
127.0.0.1 banner.fastclick.net
127.0.0.1 banners.fastclick.net
127.0.0.1 ca.com
127.0.0.1 click.atdmt.com
127.0.0.1 clicks.atdmt.com
127.0.0.1 dispatch.mcafee.com
127.0.0.1 download.mcafee.com
127.0.0.1 download.microsoft.com
127.0.0.1 downloads.microsoft.com
127.0.0.1 engine.awaps.net
127.0.0.1 fastclick.net
127.0.0.1 f-secure.com
127.0.0.1 ftp.f-secure.com
127.0.0.1 ftp.sophos.com
127.0.0.1 go.microsoft.com
127.0.0.1 liveupdate.symantec.com
127.0.0.1 mast.mcafee.com
127.0.0.1 mcafee.com
127.0.0.1 media.fastclick.net
127.0.0.1 msdn.microsoft.com
127.0.0.1 my-etrust.com
127.0.0.1 nai.com
127.0.0.1 networkassociates.com
127.0.0.1 office.microsoft.com
127.0.0.1 phx.corporate-ir.net
127.0.0.1 secure.nai.com
127.0.0.1 securityresponse.symantec.com
127.0.0.1 service1.symantec.com
127.0.0.1 sophos.com
127.0.0.1 spd.atdmt.com
127.0.0.1 support.microsoft.com
127.0.0.1 symantec.com
127.0.0.1 update.symantec.com
127.0.0.1 updates.symantec.com
127.0.0.1 us.mcafee.com
127.0.0.1 vil.nai.com
127.0.0.1 viruslist.ru
127.0.0.1 windowsupdate.microsoft.com
127.0.0.1 www.avp.ch
127.0.0.1 www.avp.com
127.0.0.1 www.avp.ru
127.0.0.1 www.awaps.net
127.0.0.1 www.ca.com
127.0.0.1 www.fastclick.net
127.0.0.1 www.f-secure.com
127.0.0.1 www.kaspersky.ru
127.0.0.1 www.mcafee.com
127.0.0.1 www.my-etrust.com
127.0.0.1 www.nai.com
127.0.0.1 www.networkassociates.com
127.0.0.1 www.sophos.com
127.0.0.1 www.symantec.com
127.0.0.1 www.trendmicro.com
127.0.0.1 www.viruslist.ru
127.0.0.1 ftp:/ /ftp.kasperskylab.ru/updates/
127.0.0.1 ftp:/ /ftp.avp.ch/updates/
127.0.0.1 http:/ /www.kaspersky.ru/updates/
127.0.0.1 http:/ /updates1.kaspersky-labs.com/updates/
127.0.0.1 http:/ /updates3.kaspersky-labs.com/updates/
127.0.0.1 http:/ /updates4.kaspersky-labs.com/updates/
127.0.0.1 http:/ /updates2.kaspersky-labs.com/updates/
127.0.0.1 http:/ /updates5.kaspersky-labs.com/updates/
127.0.0.1 http:/ /downloads1.kaspersky-labs.com/updates/
127.0.0.1 http:/ /www.kaspersky-labs.com/updates/
127.0.0.1 ftp:/ /updates3.kaspersky-labs.com/updates/
127.0.0.1 ftp:/ /downloads1.kaspersky-labs.com/updates/
127.0.0.1 www3.ca.com
127.0.0.1 ids.kaspersky-labs.com
127.0.0.1 downloads2.kaspersky-labs.com
127.0.0.1 downloads1.kaspersky-labs.com
127.0.0.1 downloads3.kaspersky-labs.com
127.0.0.1 downloads4.kaspersky-labs.com
127.0.0.1 liveupdate.symantecliveupdate.com
127.0.0.1 liveupdate.symantec.com
127.0.0.1 update.symantec.com
127.0.0.1 download.mcafee.com
127.0.0.1 www.symantec.com
127.0.0.1 securityresponse.symantec.com
127.0.0.1 symantec.com
127.0.0.1 www.sophos.com
127.0.0.1 sophos.com
127.0.0.1 www.mcafee.com
127.0.0.1 mcafee.com
127.0.0.1 liveupdate.symantecliveupdate.com
127.0.0.1 www.viruslist.com
127.0.0.1 viruslist.com
127.0.0.1 f-secure.com
127.0.0.1 kaspersky.com
127.0.0.1 kaspersky-labs.com
127.0.0.1 www.avp.com
127.0.0.1 www.kaspersky.com
127.0.0.1 avp.com
127.0.0.1 www.networkassociates.com
127.0.0.1 www.ca.com
127.0.0.1 ca.com
127.0.0.1 mast.mcafee.com
127.0.0.1 my-etrust.com
127.0.0.1 www.my-etrust.com
127.0.0.1 download.mcafee.com
127.0.0.1 dispatch.mcafee.com
127.0.0.1 secure.nai.com
127.0.0.1 nai.com
127.0.0.1 www.nai.com
127.0.0.1 update.symantec.com
127.0.0.1 updates.symantec.com
127.0.0.1 us.mcafee.com
127.0.0.1 liveupdate.symantec.com
127.0.0.1 customer.symantec.com
127.0.0.1 rads.mcafee.com
127.0.0.1 trendmicro.com
127.0.0.1 www.trendmicro.com
127.0.0.1 www.grisoft.com
therefore disables access to most AV sites.
It is interesting to mention that the worm uses the hardcoded path of the hosts file (%system32%driversetc). This path can be modified (with a simple registry setting) making this worm "feature" unusable.
The worm injects code into the Windows Explorer Application (explorer.exe). Therefore, all of the worm's malicious actions appear to be executed by the Windows Explorer.
The worm also acts as a downloader; it attempts to download a file from a set of specific hosts and execute it.
The worm also has anti-antivirus features; it attempts to delete several registry keys belonging to AV/Firewall products, as well as their services.Last update 21 November 2011