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WORM_SASSER.D
Overview

Malware type: Worm

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 2000, XP

Encrypted: No

Overall risk rating:


Reported infections:

Damage potential:

High

Distribution potential:

High

Description: 

This worm exploits the Windows LSASS vulnerability, which is a buffer overrun vulnerability that allows remote code execution and enables an attacker to gain full control of the infected system. This vulnerability is discussed in detail in the following pages:

To propagate, it scans for vulnerable systems at TCP port 445 and sends a specially-crafted packet to cause a buffer overflow on LSASS.EXE. The packet runs a remote shell that opens port 9995. This worm commands the remote shell to download its copy from the original infected source via port 5554 using FTP.

This worm can cause LSASS to crash and force Windows to restart. In this case, the following message boxes may appear:

LSA

System

Notes on Windows 2003 Server:

  • Analysis and tests done on this malware show that it can execute and create registry entries on Windows 2003 server, but it fails to exploit the LSASS service in the said operating system version.
  • Although Microsoft reports that the Windows 2003 Server is also vulnerable to the LSASS exploit, there may exist a code error within the malware exploit packet that prevents it from exploiting the LSASS vulnerability on the said platform.

The following article provides a thorough look into the different events that shaped Sasser's emergence and gives an extensive discussion about its implications:

For additional information about this threat, see:
Solution
Technical Details

Description created: May. 3, 2004 4:55:40 AM GMT -0800
Description updated: May. 6, 2004 5:22:40 AM GMT -0800

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