Sober.H appeared on June 11th, 2004. This Sober variant doesn't spread itself in e-mails. Instead, it mass-mails political statements. It might have been downloaded to computers already infected by earlier Sober variant, Sober.G for example.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
Sober.H is written in Visual Basic. Its file is a PE executable 59747 bytes long, packed with UPX file compressor. Sober.H has its own SMTP engine.
Installation to system
Sober.H's file is started installs itself to system. It copies itself to Windows System folder with a semi-randomly generated name and EXE extension. The following text strings are used to generate the file name of the Sober's executable:
sys host dir expolrer win run log 32 disc crypt data diag spool service smss32
After that Sober.H creates startup keys for its file in Windows Registry. The key names are also semi-randomly generated from the above given list. The following keys are created:
[HKCU\Software\Microsoft\Windows\CurrentVersion\Run] "<random>" = "%WinSysDir%\<random>.exe" [HKLM\Software\Microsoft\Windows\CurrentVersion\Run] "<random>" = "%WinSysDir%\<random>.exe"
During its installation cycle Sober.H creates the following files in Windows System folder:
bcegfds.lll zhcarxxi.vvx cvqaikxt.apk Odin-Anon.Ger
These files have zero length and they are used to disable previous variants of Sober if they are installed on an infected computer.
Sober.H sends different e-mail messages with political statements. It doesn't attach itself to these messages.
Before spamming Sober.H scans files with certain extensions on all hard disks to harvest e-mail addresses. Files with the following extensions are scanned:
pmr stm slk inbox imb csv bak imh xhtml imm imh cms nws vcf ctl dhtm cgi pp ppt msg jsp oft vbs uin ldb abc pst cfg mdw mbx mdx mda adp nab fdb vap dsp ade sln dsw mde frm bas adr cls ini ldif log mdb xml wsh tbb abx abd adb pl rtf mmf doc ods nch xls nsf txt wab eml hlp mht nfo php asp shtml dbx
The found e-mail addresses and user names are saved in these 2 files that Sober.H creates in Windows System folder:
When Sober.H is active in memory it blocks access to these files as well as to its executable file.
Sober.H ignores e-mail addresses that contain any of the following substrings:
@www @from. smtp- @smtp. gold-certs ftp. .dial. .ppp. anyone subscribe mantec announce @gmetref sql. someone nothing you@ user@ reciver@ somebody secure msdn. me@ whatever@ whoever@ anywhere yourname mustermann@ .kundenserver. mailer-daemon variabel -dav law2 .sul.t- .qmail@ t-ipconnect t-dialin ipt.aol time freeav @ca. abuse winrar domain. host. viren bitdefender spybot detection icrosoft ewido. emsisoft @foo. winzip @example. bellcore. @arin mozilla @iana @avp @msn @sophos @panda @kaspers free-av antivir virus verizon. @ikarus. @nai. @messagelab nlpmail01. clock
Sober.H can download and activate an executable file from the following website:
The name of the downloaded executable file is 'winhlpx32ll.exe'.
Deactivation of Sober.H
Sober.H periodically looks for a file named 'sysmms32.lla' and it this file is found, it uninstalls itself from memory. Moreover, if this file is present in Windows System folder, Sober.H does not install itself to a system.
Detection of Sober.H is available in the following FSAV updates:
Detection Type: PC
Description Created: Alexey Podrezov; June 11th, 2004