1. Skip to navigation
  2. Skip to content
  3. Skip to secondary-content




Windows Registry Editor Utility String Concealment Weakness

Report ID: SA16560
Source: Secunia
Date of Discovery: 24.08.2005
Criticality: Critical
Affects:
Microsoft Windows 2000 Advanced Server
Microsoft Windows 2000 Datacenter Server
Microsoft Windows 2000 Professional
Microsoft Windows 2000 Server
Microsoft Windows XP Home Edition
Microsoft Windows XP Professional

Compromise From: Local system
Compromise Type: Spoofing

Summary

A vulnerability has been reported in Microsoft Windows, which can be exploited to hide certain information.

Detailed Description

A vulnerability has been reported in Microsoft Windows, which can be exploited to hide certain information.

The weakness is caused due to an error in the Registry Editor Utility (regedit.exe) when handling long string names. This can be exploited to hide strings in a registry key by creating a string with a long name, which causes this string and any subsequently created strings in the key to be hidden.

Successful exploitation e.g. makes it possible for malware to hide strings in the "Run" registry key. However, these hidden strings created after the string with the overly long name will still be executed when the user logs in.

The same problem reportedly also exists for overly long registry keys.

The weakness has been confirmed in fully updated Windows XP SP2 and Windows 2000 SP4 systems. Other versions may also be affected.

NOTE: The "regedt32.exe" utility on Windows 2000 is also affected, but in a slightly different way.

NOTE: A virus is reportedly exploiting this method to hide in the registry.

Solution

It's possible to see hidden registry strings with the "reg" command line utility.

Ensure that systems have up-to-date anti-virus and spyware detection software installed.