CVE-2025-34090
Severity CVSS v4.0:
CRITICAL
Type:
Unavailable / Other
Publication date:
02/07/2025
Last modified:
03/07/2025
Description
A security bypass vulnerability exists in Google Chrome AppBound cookie encryption mechanism due to insufficient validation of COM server paths during inter-process communication. A local low-privileged attacker can hijack the COM class identifier (CLSID) registration used by Chrome&#39;s elevation service and point it to a non-existent or malicious binary. When this hijack occurs, Chrome silently falls back to the legacy cookie encryption mechanism (protected only by user-DPAPI), thereby enabling cookie decryption by any user-context malware without SYSTEM-level access. This flaw bypasses the protections intended by the AppBound encryption design and allows cookie theft from Chromium-based browsers.<br />
<br />
Confirmed in Google Chrome with AppBound Encryption enabled. Other Chromium-based browsers may be affected if they implement similar COM-based encryption mechanisms.
Impact
Base Score 4.0
9.30
Severity 4.0
CRITICAL