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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
jahlives openssl_encrypt unaffected
Version Status Constraints
0 affected < 1.4.0
1.4.0 unaffected —

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Project Subscriptions

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Advisories

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Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-w4j7-wfgw-r52w cve-icon cve-icon
https://www.vulncheck.com/advisories/openssl-encrypt-before-authentication-bypass-via-aes-ctr-fallback cve-icon cve-icon
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'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-17T11:04:59.916Z

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: 2026-08-17T11:16:45.183

Link: CVE-2026-74901

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

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

Weaknesses