openssl_encrypt versions before 1.4.0 contain an authentication bypass vulnerability in pqc.py where AES-GCM decryption failures trigger fallback to unauthenticated AES-CTR mode. Attackers can modify ciphertext in transit to bypass integrity verification and perform bit-flipping attacks without detection.
History

Mon, 17 Aug 2026 11:15:00 +0000

Type Values Removed Values Added
Description openssl_encrypt versions before 1.4.0 contain an authentication bypass vulnerability in pqc.py where AES-GCM decryption failures trigger fallback to unauthenticated AES-CTR mode. Attackers can modify ciphertext in transit to bypass integrity verification and perform bit-flipping attacks without detection.
Title openssl_encrypt before 1.4.0 Authentication Bypass via AES-CTR Fallback
Weaknesses CWE-347
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-17T16:03:16.992Z

Reserved: 2026-08-17T10:48:45.738Z

Link: CVE-2026-74901

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-17T11:16:45.183

Modified: 2026-08-17T16:17:51.187

Link: CVE-2026-74901

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-17T13:00:13Z