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CVE-2026-81020

Estado: AnalizadaAlta (7.4)—

wolfEngine before 1.4.1 generates the 8-byte explicit AES-GCM nonce once when the TLS write key is set and never increments it per record. As a result every TLS 1.2 and DTLS 1.2 AES-GCM record within a connection is encrypted under an identical key and nonce pair. Reusing a GCM key and nonce discloses the keystream (the XOR of two ciphertexts equals the XOR of their plaintexts, so one known record recovers the others) and leaks the GHASH authentication key, enabling authentication tag forgery. AES-CCM, TLS 1.3, and non-TLS use of the cipher are not affected.

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 remota en TLS 1.2/DTLS 1.2 sin autenticación (PR:N). La reutilización de nonce en AES-GCM expone el keystream y permite lectura de datos cifrados (C:H) y falsificación de etiquetas de autenticación (I:H).

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 ScanningRestrict File and Directory PermissionsPrivileged Account ManagementRemote Data StorageNetwork SegmentationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Wolfssl — Wolfengine

CWE

Referencias

JSON original (NVD)

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          "options": [
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            },
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          "userInteraction": "NONE",
          "attackComplexity": "HIGH",
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          "privilegesRequired": "NONE",
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        "exploitabilityScore": 2.2
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          "vendor": "wolfSSL Inc.",
          "product": "wolfEngine",
          "versions": [
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  "published": "2026-08-28T16:18:28.890",
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      ],
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    }
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    }
  ],
  "lastModified": "2026-09-29T19:10:21.303",
  "configurations": [
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