openssl_encrypt before 1.4.0 Weak Shared Secret via PQC Simulation Mode
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
openssl_encrypt versions before 1.4.0 contain a critical vulnerability in pqc.py where KEM decapsulation failures silently fall back to simulation mode, generating a deterministic shared secret from only 16 bytes of the private key and publicly available encapsulated key data. Attackers who obtain 16 bytes of the private key can compute the shared secret and decrypt all ciphertext, as the fallback triggers on any KEM failure without raising an error.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA openssl_encrypt (jahlives) Fixed in 1.4.0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
jahlives openssl_encrypt 1.4.0
28 records Highest priority Priority HIGH 3 HIGH, 21 MEDIUM, 4 LOW
Other records, highest priority first
- TI-2026-52616 openssl_encrypt before 1.4.0 Sandbox Escape via Type HierarchyPriority HIGH 81
- TI-2026-52615 openssl_encrypt before 1.4.0 Sandbox Escape via Dunder Attribute TraversalPriority HIGH 81
- TI-2026-52602 openssl_encrypt before 1.4.0 Sandbox Bypass via pathlib and ioPriority HIGH 79
Timeline
- 2026-10-02 Threatist record created from CVE-2026-74900
- 2026-10-03 Alias added: GHSA-7qj7-jv8m-rfjw
References
More jahlives Openssl Encrypt vulnerabilities
- TI-2026-52616 openssl_encrypt before 1.4.0 Sandbox Escape via Type Hierarchy CVSS 4.0CRITICAL 9.3
- TI-2026-52615 openssl_encrypt before 1.4.0 Sandbox Escape via Dunder Attribute Traversal CVSS 4.0CRITICAL 9.3
- TI-2026-52602 openssl_encrypt before 1.4.0 Sandbox Bypass via pathlib and io CVSS 4.0HIGH 8.7
- TI-2026-52614 openssl_encrypt before 1.4.0 Plugin Sandbox Bypass via Process Isolation CVSS 4.0CRITICAL 9.3
- TI-2026-52613 openssl_encrypt before 1.4.0 Authentication Bypass via Bearer Token CVSS 4.0CRITICAL 9.3
- TI-2026-52605 openssl_encrypt before 1.4.0 Plugin Import Guard Bypass CVSS 4.0CRITICAL 9.3
Sources
- CVE-2026-74900 · CVE Program
- CVE-2026-74900 · NVD
- FIRST EPSS
- GHSA-7qj7-jv8m-rfjw · GitHub Advisory Database · CC BY 4.0
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