Virus: Worm/Yahos.mg Date discovered: 28/01/2011 Type: Worm Subtype: BE9C85C24390BD527C57CC1AA59A4241 In the wild: Yes Reported Infections: Medium Distribution Potential: Low to medium Damage Potential: Medium Static file: Yes File size: 94.208 Bytes VDF version: 7.10.08.76 IVDF version: 7.11.02.17 - Friday, January 28, 2011
General Method of propagation: • Messenger Aliases: • Mcafee: W32/Sdbot.bfr!a • Kaspersky: IM-Worm.Win32.Yahos.mg • TrendMicro: WORM_YAHOS.AM • F-Secure: Worm:W32/Slenfbot.AGV • Sophos: W32/Agent-QEF • Microsoft: Worm:Win32/Slenfbot.AKD • Panda: W32/Lolbot.Q.worm • VirusBuster: Worm.Yahos!uzwHWUDAUIg • DrWeb: BackDoor.IRC.Bot.763 • Norman: W32/Slenfbot.T Platforms / OS: • Windows 95 • Windows 98 • Windows 98 SE • Windows ME • Windows 2000 • Windows XP • Windows 2003 • Windows Vista • Windows Server 2008 • Windows 7 Side effects: • Drops files • Lowers security settings • Records keystrokes • Registry modification • Opens website in web browser Files It copies itself to the following location: • %WINDIR% \nvsvc32.exe The following files are created: – Non malicious files: • %WINDIR% \ndl.dl • %WINDIR% \wiybr.png • %WINDIR% \wibrf.jpg It tries to execute the following files: – Filename: • %SYSDIR% \net.exe – Filename: • %SYSDIR% \netsh.exe using the following command line arguments: firewall add allowedprogram 1.exe 1 ENABLE – Filename: • %SYSDIR% \ntvdm.exe – Filename: • %SYSDIR% \sc.exe using the following command line arguments: config wuauserv start= disabled – Filename: • %SYSDIR% \sc.exe using the following command line arguments: config MsMpSvc start= disabled – Filename: • %WINDIR% \nvsvc32.exe – Filename: • %WINDIR% \explorer.exe using the following command line arguments: http://browseusers.myspa**********.com/Browse/Browse.aspx Registry The following registry key is added in order to run the process after reboot: – [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] • "NVIDIA driver monitor"="%WINDIR% \nvsvc32.exe" – [HKCU\Software\Microsoft\Windows\CurrentVersion\Run] • "NVIDIA driver monitor"="%WINDIR% \nvsvc32.exe" – [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Terminal Server\ Install\Software\Microsoft\Windows\CurrentVersion\Run] • "NVIDIA driver monitor"="%WINDIR% \nvsvc32.exe" It creates the following entry in order to bypass the Windows XP firewall: – [HKLM\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\ FirewallPolicy\StandardProfile\AuthorizedApplications\List] • "%malware execution directory% \%executed file% "="%WINDIR% \nvsvc32.exe:*:Enabled:NVIDIA driver monitor" The following registry keys are changed: – [HKCR\TypeLib\%CLSID% \1.1\0\win32] New value: • "(Default)"="oleacc.dll" Lower security settings from Internet Explorer: – [HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ ZoneMap] Old value: • "ProxyBypass"=%user defined settings% • "IntranetName"=%user defined settings% • "UNCAsIntranet"=%user defined settings% New value: • "ProxyBypass"=dword:00000001 • "IntranetName"=dword:00000001 • "UNCAsIntranet"=dword:00000001 – [HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings] Old value: • "MigrateProxy"=%user defined settings% • "ProxyEnable"=%user defined settings% New value: • "MigrateProxy"=dword:00000001 • "ProxyEnable"=dword:00000000 – [HKEY_CURRENT_CONFIG\Software\Microsoft\windows\CurrentVersion\ Internet Settings] Old value: • "ProxyEnable"=%user defined settings% New value: • "ProxyEnable"=dword:00000000 Messenger It is spreading via Messenger. The characteristics are described below: – Yahoo Messenger Message The sent message looks like the following: • %message text% :D http://yrtadelozie********** IRC To deliver system information and to provide remote control it connects to the following IRC Server: Server: %IRC server% Port: 1234 Server password: xxx Channel: #!nn!********** Nickname: NEW-[GBR|00|**********|%random numbers% ] – Furthermore it has the ability to perform actions such as: • connect to IRC server • disconnect from IRC server • Join IRC channel Miscellaneous Internet connection: It queries with the following names: • astro.ic.**********.uk • ale.pakibi**********.com • versat**********.com • journalofaccountan**********.com • transnationa**********.org • mas.0730**********.com • api.albertoshisto**********.info • stayonti**********.info • www.shearm**********.com • insidehigher**********.com • ate.lacoctele**********.net • websitetraffics**********.com • qun.5**********.com • summer-uni-sw.**********.ch • shopsty**********.com • xxx.stopklat**********.pl • unclef**********.com • mcsp.lvengi**********.com • www.facebo**********.com • browseusers.myspa**********.com • www.myspa**********.com • x.myspacec**********.com • deirdremcclosk**********.org • journals.l**********.com • middleastpo**********.org • mas.archiv**********.info • scribbidyscru**********.com • mas.mtim**********.com • ols.systemofado**********.com Accesses internet resources: • http://www.facebo**********.com/home.php; http://www.facebo**********.com/login.php; http://browseuse**********.myspace.com/Browse/Browse.aspx; http://www.myspa**********.com/browse/people; http://www.myspa**********.com/help/browserunsupported; http://x.myspace**********.com/modules/splash/static/img/cornersSheet.png; http://x.myspacec**********.com/images/BrowserUpgrade/bg_infobox.jpg; http://x.myspace**********.com/images/BrowserUpgrade/icon_information.gif; http://x.myspace**********.com/images/BrowserUpgrade/bg_browserSection.jpg; http://x.myspace**********.com/images/BrowserUpgrade/browserLogos_med.jpg; http://174.37.200.**********/index.php File details Programming language: The malware program was written in MS Visual C++. Compilation date: Date: 27/01/2011 Time: 15:03:49
Description inserted by Alexander Bauer on Monday, January 31, 2011 Description updated by Alexander Bauer on Monday, January 31, 2011
Back
.
.
.
.