CVE-2021-29921
Estado: ModificadaCrítica (9.8)—
In Python before 3,9,5, the ipaddress library mishandles leading zero characters in the octets of an IP address string. This (in some situations) allows attackers to bypass access control that is based on IP addresses.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 6.88%
- Percentil entre todas las CVEs puntuadas: 94
- 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
- NVD-CWE-Other
Referencias
- https://bugs.python.org/issue36384
- https://docs.python.org/3/library/ipaddress.html
- https://github.com/python/cpython/blob/63298930fb531ba2bb4f23bc3b915dbf1e17e9e1/Misc/NEWS.d/3.8.0a4.rst
- https://github.com/python/cpython/pull/12577
- https://github.com/python/cpython/pull/25099
- https://github.com/sickcodes
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.md
- https://python-security.readthedocs.io/vuln/ipaddress-ipv4-leading-zeros.html
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20210622-0003/
- https://sick.codes/sick-2021-014
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://bugs.python.org/issue36384
- https://docs.python.org/3/library/ipaddress.html
- https://github.com/python/cpython/blob/63298930fb531ba2bb4f23bc3b915dbf1e17e9e1/Misc/NEWS.d/3.8.0a4.rst
- https://github.com/python/cpython/pull/12577
- https://github.com/python/cpython/pull/25099
- https://github.com/sickcodes
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.md
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
- https://python-security.readthedocs.io/vuln/ipaddress-ipv4-leading-zeros.html
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20210622-0003/
- https://sick.codes/sick-2021-014
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
JSON original (NVD)
Mostrar
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