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CVE-2026-74900

Estado: AnalizadaCrítica (9.3)—

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.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Vulnerabilidad en servicio remoto sin autenticación (AV:N/PR:N/UI:N). El fallback silencioso del KEM permite derivar la clave compartida con solo 16 bytes de clave privada, exponiendo material criptográfico y permitiendo descifrado de datos.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability ScanningUser TrainingRestrict File and Directory PermissionsPrivileged Account ManagementPassword PoliciesNetwork Segmentation

Tecnologías afectadas (1)

Jahlives — Openssl Encrypt

CWE

Referencias

JSON original (NVD)

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