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.
History

Wed, 02 Jul 2025 21:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 02 Jul 2025 19:30:00 +0000

Type Values Removed Values Added
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.
Title Google Chrome AppBound Cookie Encryption Bypass via COM Hijacking
Weaknesses CWE-276
CWE-426
References
Metrics cvssV4_0

{'score': 9.3, 'vector': '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2025-07-02T19:25:13.805Z

Updated: 2025-07-03T03:55:39.005Z

Reserved: 2025-04-15T19:15:22.551Z

Link: CVE-2025-34090

cve-icon Vulnrichment

Updated: 2025-07-02T19:57:35.790Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-07-02T20:15:30.110

Modified: 2025-07-03T15:13:53.147

Link: CVE-2025-34090

cve-icon Redhat

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