- Threat Encyclopedia
- Malware
- BKDR_POISON
Windows 2000, Windows XP, Windows Server 2003
This description is based on a compiled analysis of several variants of BKDR_POISON. Note that specific data such as file names and registry values may vary for each variant.
This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
It uses legitimate program icons for its attachments to trick users into thinking they are harmless.
Varies
Yes
27 Oct 2011
Arrival Details
This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
Installation
This backdoor adds the following mutexes to ensure that only one of its copies runs at any one time:
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random GUID}
StubPath = "{malware path and file name"
Propagation
This backdoor uses the following program icons for its attachments:
Backdoor Routine
This backdoor connects to the following URL(s) to send and receive commands from a remote malicious user:
NOTES:
It queries the default web browser by accessing the following registry entry:
HKEY_CLASSES_ROOT\http\shell\open\command
It then launches a hidden Web browser process (e.g. iexplore.exe). The malware then injects its code to the said process, which contains its backdoor routines.
This backdoor has the following capabilities:
Other Details
This malware may arrive contained inside a self extracting archive (RAR SFX) and attached in email messages.
The SFX drops and executes this malware as any but not limited to the following:
(Note:%User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)
The SFX also drops any of the following encrypted component files:(Note:%User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)
Upon execution, it checks for the account user of the affected system if it has administrator rights.
If yes, it copies itself to an alternate data stream (ADS) or as physical file in the %System% directory. Their file names vary depending on the sample.
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
It the user has no administrator rights, it copies itself as any of the following:
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
It copies the encrypted component files as to the following:
(Note:%Program Files% is the default Program Files folder, usually C:\Program Files. %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.%Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
It stays memory resident by injecting codes in the following process:
This description is based on a compiled analysis of several variants of BKDR_POISON. Note that specific data such as file names and registry values may vary for each variant.
9.200
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