CVE-2021-20305
Estado: ModificadaAlta (8.1)—
A flaw was found in Nettle in versions before 3.7.2, where several Nettle signature verification functions (GOST DSA, EDDSA & ECDSA) result in the Elliptic Curve Cryptography point (ECC) multiply function being called with out-of-range scalers, possibly resulting in incorrect results. This flaw allows an attacker to force an invalid signature, causing an assertion failure or possible validation. The highest threat to this vulnerability is to confidentiality, integrity, as well as system availability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.69%
- Percentil entre todas las CVEs puntuadas: 76
- Fecha de la puntuación: 6/10/2026
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 (6)
CWE
- CWE-327
- CWE-787
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1942533
- https://lists.debian.org/debian-lts-announce/2021/09/msg00008.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MQKWVVMAIDAJ7YAA3VVO32BHLDOH2E63/
- https://security.gentoo.org/glsa/202105-31
- https://security.netapp.com/advisory/ntap-20211022-0002/
- https://www.debian.org/security/2021/dsa-4933
- https://bugzilla.redhat.com/show_bug.cgi?id=1942533
- https://lists.debian.org/debian-lts-announce/2021/09/msg00008.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MQKWVVMAIDAJ7YAA3VVO32BHLDOH2E63/
- https://security.gentoo.org/glsa/202105-31
- https://security.netapp.com/advisory/ntap-20211022-0002/
- https://www.debian.org/security/2021/dsa-4933
JSON original (NVD)
Mostrar
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