CVE-2018-6829
Estado: ModificadaAlta (7.5)—
cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for Libgcrypt's ElGamal implementation.
CVSS
- Versión: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.78%
- Percentil entre todas las CVEs puntuadas: 77
- Fecha de la puntuación: 2/10/2026
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).
Tecnologías afectadas (1)
CWE
- CWE-327
Referencias
- https://github.com/weikengchen/attack-on-libgcrypt-elgamal
- https://github.com/weikengchen/attack-on-libgcrypt-elgamal/wiki
- https://lists.gnupg.org/pipermail/gcrypt-devel/2018-February/004394.html
- https://www.oracle.com/security-alerts/cpujan2020.html
- https://github.com/weikengchen/attack-on-libgcrypt-elgamal
- https://github.com/weikengchen/attack-on-libgcrypt-elgamal/wiki
- https://lists.gnupg.org/pipermail/gcrypt-devel/2018-February/004394.html
- https://www.oracle.com/security-alerts/cpujan2020.html
JSON original (NVD)
Mostrar
{
"id": "CVE-2018-6829",
"cveTags": [],
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"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "NONE",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
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"integrityImpact": "NONE",
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"affected": [
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"published": "2018-02-07T23:29:01.703",
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"vulnStatus": "Modified",
"weaknesses": [
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"source": "nvd@nist.gov",
"description": [
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"value": "cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for Libgcrypt's ElGamal implementation."
},
{
"lang": "es",
"value": "cipher/elgamal.c en Libgcrypt hasta la versión 1.8.2, al emplearse para cifrar mensajes directamente, cifra los textos planos indebidamente, lo que permite que atacantes remotos obtengan información sensible mediante la lectura de datos en texto cifrado (p.ej., no tiene seguridad semántica a la hora de enfrentarse a un ataque solo en texto cifrado). La hipótesis DDH (Decisional Diffie-Hellman) no soporta la implementación ElGamal de Libgcrypt."
}
],
"lastModified": "2026-06-17T02:02:19.757",
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