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.be TEMP folder is vulnerable to DLL redirection attacks that allow the attacker to escalate privileges

High
robmen published GHSA-7wh2-wxc7-9ph5 Feb 7, 2024

Package

nuget wix (NuGet)

Affected versions

>= 4, < 4.0.4
< 3.14.0

Patched versions

4.0.4
3.14.0

Description

Summary

.be TEMP folder is vulnerable to DLL redirection attacks that allow the attacker to escalate privileges.

Details

If the bundle is not run as admin, the user's TEMP folder is used and not the system TEMP folder. A utility is able to monitor the user's TEMP folder for changes and drop its own DLL into the .be/.Local folder immediately when the .be folder is created. When the burn engine elevates, the malicious DLL receives elevated privileges.

PoC

As a standard, non-admin user:

  1. Monitor the user's TEMP folder for changes using ReadDirectoryChangesW
  2. On FILE_ACTION_ADDED, check if the folder name is .be
  3. Create a folder in .be named after the bundle + .Local (e.g. MyInstaller.exe.Local)
  4. Put the malicious COMCTL32.DLL in the .Local folder following the naming used for the real DLL (e.g. MyInstaller.exe.Local/x86_microsoft.windows.common-controls_.../COMCTL32.dll)
  5. Do hacker things when the engine escalates and the malicious DLL is loaded

Proper naming for the path can be obtained by using GetModuleHandle("comctl32.dll") and GetModuleFileName.

Impact

DLL redirection utilizing .exe.Local Windows capability. This impacts any installer built with the WiX installer framework.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

CVE ID

CVE-2024-24810

Weaknesses

No CWEs