CVE-2026-1502 - Vulnerability Details - OpenCVE

CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.

Attack Vector Network

Attack Complexity Low

Privileges Required High

Attack Requirements Present

User Interaction Passive

Vulnerable System Confidentiality Impact None

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	< 3.15.0

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/commit/05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69
https://github.com/python/cpython/issues/146211
https://github.com/python/cpython/pull/146212
https://mail.python.org/archives/list/security-announce@python.org/thread/2IVPAEQWUJBCTQZEJEVTYCIKSMQPGRZ3/

History

Fri, 10 Apr 2026 18:15:00 +0000

Type	Values Removed	Values Added
Description		CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
Title		HTTP client proxy tunnel headers not validated for CR/LF
References		https://github.com/python/cpython/commit/05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69 https://github.com/python/cpython/issues/146211 https://github.com/python/cpython/pull/146212 https://mail.python.org/archives/list/security-announce@python.org/thread/2IVPAEQWUJBCTQZEJEVTYCIKSMQPGRZ3/
Metrics		cvssV4_0 `{'score': 5.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: PSF

Published: 2026-04-10T17:54:44.121Z

Updated: 2026-04-10T17:59:40.856Z

Reserved: 2026-01-27T19:10:37.711Z

Link: CVE-2026-1502

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-04-10T18:16:40.970

Modified: 2026-04-10T18:16:40.970

Link: CVE-2026-1502

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

No weakness.

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