Critical · CVSS 9.3CVE-2026-74901

openssl_encrypt before 1.4.0 Authentication Bypass via AES-CTR Fallback

Answer in brief

CVE-2026-74901 records a Critical severity (CVSS 9.3) vulnerability in openssl_encrypt before 1.4.0 Authentication Bypass via AES-CTR Fallback. The current sources do not mark it as known exploited. The current feed maps jahlives/openssl_encrypt (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 17, 2026Updated Oct 1, 2026Source checked Oct 1, 2026First seen by HOL Aug 17, 2026Material review Oct 1, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.3
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 9.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps jahlives/openssl_encrypt (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
Product	Affected versions	Fixed versions
cpe:2.3:a:jahlives:openssl_encrypt::::::python::*	Not reported	Not reported

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
jahlives/openssl_encryptgeneric	>=0 <1.4.0	1.4.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for jahlives/openssl_encrypt.
Review the reported fix. Update jahlives/openssl_encrypt to 1.4.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 1, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 17, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.