CVE-2018-20187
Estado: ModificadaMedia (5.9)—
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
CVSS
- Versión: 3.0
- Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 5.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.52%
- Percentil entre todas las CVEs puntuadas: 74
- Fecha de la puntuación: 5/10/2026
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-320
Referencias
JSON original (NVD)
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"published": "2019-03-08T19:29:00.250",
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"lastModified": "2026-06-17T01:52:25.623",
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