Analysis by: Jasen Sumalapao
ALIASES:

Exploit:JS/ShellCode.AT (Microsoft), Hacktool.IE.Exploit (Symantec), Exp/20121889-A (Sophos), Exploit.HTML.CVE-2012-1889 (v) (Sunbelt), JS/ShellCode.BAAC!exploit (Fortinet)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Spammed via email, Dropped by other malware, Downloaded from the Internet

This malware exploits the vulnerability in Microsoft XML Core Services, which prompted Microsoft to release a fix tool.

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

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites. It executes when a user accesses certain websites where it is hosted.

It takes advantage of software vulnerabilities to allow a remote user or malware/grayware to download files. It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Once a user visits an affected Web page, this HTML script launches a hidden IFRAME that connects to a malicious URL. This is the Trend Micro detection for Web pages that were compromised through the insertion of a certain IFRAME tag.

  TECHNICAL DETAILS

File Size: 12,063 bytes
File Type: HTML, HTM
Initial Samples Received Date: 26 Jun 2012
Payload: Downloads files

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It executes when a user accesses certain websites where it is hosted.

Download Routine

This Trojan connects to the following website(s) to download and execute a malicious file:

  • http://{BLOCKED}ia.co.in/css/css.exe - detected as BKDR_POISON.HUQA

It takes advantage of the following software vulnerabilities to allow a remote user or malware/grayware to download files:

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

Other Details

Once a user visits an affected Web page, this HTML script launches a hidden IFRAME that connects to a malicious URL.

It inserts the following code:

  • http://www.{BLOCKED}9.com.hk

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 9.218.02
FIRST VSAPI PATTERN DATE: 26 Jun 2012
VSAPI OPR PATTERN File: 9.219.00
VSAPI OPR PATTERN Date: 27 Jun 2012

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

Remove malware files dropped/downloaded by HTML_EXPLOYT.AE

    • BKDR_POISON.HUQA

Step 3

Scan your computer with your Trend Micro product to delete files detected as HTML_EXPLOYT.AE. 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 this security patch 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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