CVE-2021-28363
Estado: ModificadaMedia (6.5)—
The urllib3 library 1.26.x before 1.26.4 for Python omits SSL certificate validation in some cases involving HTTPS to HTTPS proxies. The initial connection to the HTTPS proxy (if an SSLContext isn't given via proxy_config) doesn't verify the hostname of the certificate. This means certificates for different servers that still validate properly with the default urllib3 SSLContext will be silently accepted.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 2.11%
- Percentil entre todas las CVEs puntuadas: 81
- Fecha de la puntuación: 1/10/2026
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 (3)
CWE
- CWE-295
Referencias
- https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0
- https://github.com/urllib3/urllib3/commits/main
- https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2r
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/
- https://pypi.org/project/urllib3/1.26.4/
- https://security.gentoo.org/glsa/202107-36
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20240621-0007/
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0
- https://github.com/urllib3/urllib3/commits/main
- https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2r
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/
- https://pypi.org/project/urllib3/1.26.4/
- https://security.gentoo.org/glsa/202107-36
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20240621-0007/
- https://www.oracle.com/security-alerts/cpuoct2021.html
JSON original (NVD)
Mostrar
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