WORM_SWISYN.FT
Backdoor.Cycbot (Symantec); Swisyn.ae (Mcafee); Troj/Agent-PZT (Sophos)
Windows 2000, XP, Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It drops copies of itself in all removable drives. It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
TECHNICAL DETAILS
Arrival Details
This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Installation
This worm drops the following copies of itself into the affected system:
- %Application Data%\C575E8A8-16E2-4C95-AE36-0BA9C90710B0\rundll32.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
It creates the following folders:
- %Application Data%\C575E8A8-16E2-4C95-AE36-0BA9C90710B0
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
C575E8A8-16E2-4C95-AE36-0BA9C90710B0 = "%Application Data%\C575E8A8-16E2-4C95-AE36-0BA9C90710B0\rundll32.exe"
Propagation
This worm drops copies of itself in all removable drives.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
The said .INF file contains the following strings:
[AutoRun]
action=Explore USB-drive files
shellexecute=compacu.exe
UseAutoPlay=1
icon=compacu.exe
NOTES:
It may use any of the following file names for its dropped copies in removable drives:
- Alicia.exe
- Angelina.exe
- Britney.exe
- Keira.exe
- Kelly.exe
- Kristen.exe
- Liz_Hurley.exe
- Madonna.exe
- Scarlett_Johansson.exe
- Stephanie.exe
It also drops the following files in removable drives:
- compacu.dll
- compacu.exe
- Shortcut to {letter}.lnk