01642 06 11 11 Arrange Call

IP Address Access Control Bypass Vulnerability in Python's ipaddress Library

CVE-2021-29921 · CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVE-2021-29921

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.

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