ALIASES:

Worm:Win32/Pushbot.NM (Microsoft); Net-Worm.Win32.Mytob.rl, Net-Worm.Win32.Mytob.rl (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.2427035 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • 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 modifies files, disabling programs and applications from properly running.

  TECHNICAL DETAILS

File Size: 249,856 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 18 Jun 2012

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.

Other System Modifications

This worm modifies the following files:

  • %User Profile%\Application Data\Microsoft

(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.)

Dropping Routine

This worm drops the following files:

  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-4025279379-4087772427-2915903831-500

(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.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.200

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Search and delete these files

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Profile%\Microsoft\Crypto
  • %User Profile%\Crypto\RSA
  • %User Profile%\RSA\S-1-5-21-4025279379-4087772427-2915903831-500

Step 3

Scan your computer with your Trend Micro product to delete files detected as WORM_IRCBOT.CFL. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 4

Restore deleted/modified files and/or registry entries from backup

*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

    • %User Profile%\Application Data\Microsoft


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