Advisory Details

January 15th, 2025

Microsoft Windows Installer Service Link Following Local Privilege Escalation Vulnerability

ZDI-25-029
ZDI-CAN-25332

CVE ID CVE-2025-21331
CVSS SCORE 7.8, AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AFFECTED VENDORS Microsoft
AFFECTED PRODUCTS Windows
VULNERABILITY DETAILS

This vulnerability allows local attackers to escalate privileges on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.

The specific flaw exists within the Windows Installer service. By creating a mount point, an attacker can abuse the service to delete arbitrary files. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of SYSTEM.

ADDITIONAL DETAILS Microsoft has issued an update to correct this vulnerability. More details can be found at:
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21331
DISCLOSURE TIMELINE
  • 2024-09-10 - Vulnerability reported to vendor
  • 2025-01-15 - Coordinated public release of advisory
  • 2025-01-15 - Advisory Updated
CREDIT Simon Zuckerbraun - Trend Micro Zero Day Initiative
BACK TO ADVISORIES