CVE-2021-29921
- State
- Published
- Severity
- Not scored
- Published
- May 6, 2021
- Updated
- Oct 8, 2026
- Reserved
- Apr 1, 2021
Description
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.
Scores
The record has no CVSS score.
Weaknesses
The record names no weakness.
Affected Products
| Product | Versions |
|---|---|
n/an/a |
|
References
- https://github.com/sickcodes
- https://docs.python.org/3/library/ipaddress.html
- https://github.com/python/cpython/blob/63298930fb531ba2bb4f23bc3b915dbf1e17e9e1/Misc/NEWS.d/3.8.0a4.rst
- https://sick.codes/sick-2021-014
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-014.md
- https://python-security.readthedocs.io/vuln/ipaddress-ipv4-leading-zeros.html
- https://bugs.python.org/issue36384
- https://github.com/python/cpython/pull/12577
- https://github.com/python/cpython/pull/25099
- https://security.netapp.com/advisory/ntap-20210622-0003/
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
- GLSA-202305-02vendor-advisory
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
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