PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

ZAPCHAST variants often arrive as an attachment to spammed messages. Once the malware has been executed, it creates a backdoor which gives an attacker access to the infected computer. It can also download and execute arbitrary files, and update itself. Variants may also check for AV-related files in the infected computer.

Some ZAPCHAST variants use an IRC client to perform backdoor routines.

This backdoor executes commands from a remote malicious user, effectively compromising the affected system.

It deletes itself after execution.

  TECHNICAL DETAILS

Residente en memoria Yes

Installation

This backdoor drops the following copies of itself into the affected system:

  • %System%\sve.exe
  • %System%\ccape.exe
  • %System%\ccwap.exe

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • PpPPpPPpPPpPPpPPpP

Other System Modifications

This backdoor adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random}

It adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{random}
StubPath = "%System%\sve.exe 1 2"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Adobe_RLX = "%System%\sve.exe 1 2"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
avatar = "%System%\ccape.exe 1 2"

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

  • Download file
  • Download and execute file
  • Update itself
  • Perform remote shell command

Other Details

This backdoor connects to the following possibly malicious URL:

  • {BLOCKED}g.{BLOCKED}L.com
  • {BLOCKED}t.{BLOCKED}b.com
  • {BLOCKED}1.{BLOCKED}m.info
  • {BLOCKED}jia.{BLOCKED}ip.net
  • www.{BLOCKED}ver.{BLOCKED}o.com
  • ftp.{BLOCKED}ver.{BLOCKED}o.com

It deletes itself after execution.

NOTES:

It searches for the following AV-related files:

  • ESET
  • Avira
  • Trend Micro
  • AVAST
  • McAfee
  • Panda Security
  • AVG
  • Kaspersky
  • Symantec
  • Norton