CVE-2025-34090

Published Jul 2, 2025

Last updated 15 days ago

Overview

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'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. Confirmed in Google Chrome with AppBound Encryption enabled. Other Chromium-based browsers may be affected if they implement similar COM-based encryption mechanisms.
Source
disclosure@vulncheck.com
NVD status
Awaiting Analysis

Risk scores

CVSS 4.0

Type
Secondary
Base score
9.3
Impact score
-
Exploitability score
-
Vector string
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity
CRITICAL

Weaknesses

disclosure@vulncheck.com
CWE-276

Social media

Hype score
Not currently trending