CVE-2026-116566 - Vulnerability Details - OpenCVE

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

Attack Vector Adjacent Network

Attack Complexity Low

Privileges Required High

Attack Requirements Present

User Interaction Passive

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Python Software Foundation

CPython

unaffected

Version	Status	Constraints
`0`	affected	< 3.16.0

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://github.com/python/cpython/issues/160898
https://github.com/python/cpython/pull/160899
https://mail.python.org/archives/list/security-announce@python.org/thread/HCHE62VYTPYI6WOPJQDWUBR4CINBPSM7/

History

Thu, 29 Oct 2026 18:00:00 +0000

Type	Values Removed	Values Added
Description		socket.getaddrinfo() previously accepted null bytes within host and port parameters which can cause the values to be silently truncated.
Title		socket.getaddrinfo() accepts embedded null bytes in host and port
Weaknesses		CWE-158
References		https://github.com/python/cpython/issues/160898 https://github.com/python/cpython/pull/160899 https://mail.python.org/archives/list/security-announce@python.org/thread/HCHE62VYTPYI6WOPJQDWUBR4CINBPSM7/
Metrics		cvssV4_0 `{'score': 5.3, 'vector': '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'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: PSF

Published: 2026-10-29T17:45:47.583Z

Updated: 2026-10-29T17:47:23.422Z

Reserved: 2026-10-26T15:00:04.249Z

Link: CVE-2026-116566

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-10-29T18:17:24.667

Modified: 2026-10-29T18:17:24.667

Link: CVE-2026-116566

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-158

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