Analysis by: Michael Cabel

ALIASES:

Exploit:Java/CVE-2013-0431 (Microsoft); Java.Exploit.CVE-2013-0422.C (F-Secure)

 PLATFORM:

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

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This malware exploits vulnerabilities related to CVE-2013-0431.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan may arrive bundled with malware packages as a malware component. It may be hosted on a website and run when a user accesses the said website.

  TECHNICAL DETAILS

File Size: Varies
File Type: Java Class
Initial Samples Received Date: 21 Feb 2013
Payload: Downloads files

Arrival Details

This Trojan may arrive bundled with malware packages as a malware component.

It may be hosted on a website and run when a user accesses the said website.

Download Routine

This Trojan takes advantage of the following software vulnerabilities to download possibly malicious files:

It saves the files it downloads using the following names:

  • %User Profile%\{Random File Name}.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

It downloads a possibly malicious file from a certain URL. The URL where this malware downloads the said file depends on the following parameter(s) passed on to it by its components:

  • val
  • prime

Other Details

This Trojan executes the downloaded file using the following commands:

  • regsvr32 -s %User Profile%\{file name}.exe
  • %User Profile%\{file name}.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

  SOLUTION

Minimum Scan Engine: 9.300
FIRST VSAPI PATTERN FILE: 9.744.01
FIRST VSAPI PATTERN DATE: 21 Feb 2013
VSAPI OPR PATTERN File: 9.745.00
VSAPI OPR PATTERN Date: 21 Feb 2013

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Close all opened browser windows

Step 3

Scan your computer with your Trend Micro product to delete files detected as JAVA_EXPLOIT.CVE. 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

Download and apply these security patches Refrain from using these products until the appropriate patches have been installed. Trend Micro advises users to download critical patches upon release by vendors.


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