CVE-2026-116566

socket.getaddrinfo() accepts embedded null bytes in host and port

State: Published
Severity: 5.3 Medium
Published: Oct 29, 2026
Updated: Oct 29, 2026
Reserved: Oct 26, 2026

Description

socket.getaddrinfo() previously accepted null bytes within *host* and *port* parameters which can cause the values to be silently truncated.

Scores

CVSS	Score	Vector	Source
4.0	5.3 Medium	CVSS:4.0/AV:A/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N	PSF

Weaknesses

CWE-158

Affected Products

Product	Versions
CPythonPython Software Foundation	before 3.16.0Affected

References

https://github.com/python/cpython/pull/160899patch
https://github.com/python/cpython/issues/160898issue-tracking
https://mail.python.org/archives/list/security-announce@python.org/thread/HCHE62VYTPYI6WOPJQDWUBR4CINBPSM7/vendor-advisory
http://www.openwall.com/lists/oss-security/2026/10/29/4

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