Submission Summary:

What's been foundSeverity Level
Downloads/requests other files from Internet.
Modifies some system settings that may have negative impact on overall system security state.
Creates a startup registry entry.
Contains characteristics of an identified security risk.


Technical Details:


Possible Security Risk

Security RiskDescription
Email-Worm.Brontok!sd5 Email-Worm.Brontok!sd5 is a mass-mailing application that propagates from one system to another by creating a new email message, attaching itself and then sending the message without user's consent.
Email-Worm.Brontok.Q Email.Worm.Brontok.Q is an email worm that propagates by sending itself to email contacts harvested from an infected machine. This worm employs several anti-removal tactics that will cause a system reboot when triggered.

Threat CategoryDescription
A network-aware worm that attempts to replicate across the existing network(s)


File System Modifications

#Filename(s)File SizeFile HashAlias
1 %AppData%\csrss.exe
[file and pathname of the sample #1]
%System%\%UserName%'s Setting.scr
42,667 bytes MD5: 0xEF44B817DCEB4C3BFD21FD3D08B5D28D
SHA-1: 0x5CFE3E6816B989C1DDC1415DD7A257D41A0FBF74
W32.Rontokbro@mm [Symantec]
Email-Worm.Win32.Brontok.q [Kaspersky Lab]
W32/Rontokbro.gen@MM [McAfee]
W32/Brontok-Gen, Mal/Packer, Mal/EncPk-BA [Sophos]
Worm:Win32/Brontok@mm [Microsoft]
Email-Worm.Win32.Brontok [Ikarus]
Win32/Brontok.worm.42667 [AhnLab]
2 %Windir%\Tasks\At1.job 406 bytes MD5: 0x69CC5A90F4B503986B1B8437DA944672
SHA-1: 0x5FA6A8B0739A8483CD6BC300B54CD0A4EBBCDB39
(not available)


Memory Modifications

Process NameProcess FilenameMain Module Size
winlogon.exe%AppData%\winlogon.exe253,952 bytes
services.exe%AppData%\services.exe253,952 bytes
lsass.exe%AppData%\lsass.exe253,952 bytes
csrss.exe%AppData%\csrss.exe253,952 bytes
inetinfo.exe%AppData%\inetinfo.exe253,952 bytes
[filename of the sample #1][file and pathname of the sample #1]253,952 bytes
smss.exe%AppData%\smss.exe253,952 bytes


Registry Modifications


Other details



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