CVE-2026-0865

User-controlled header names and values containing newlines can allow injecting HTTP headers.

CVSS

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/22e4d55285cee52bc4dbe061324e5f30bd4dee58
https://github.com/python/cpython/commit/23e3c0ae867cca0130e441e776c9955b9027c510
https://github.com/python/cpython/commit/2f840249550e082dc351743f474ba56da10478d2
https://github.com/python/cpython/commit/4802b96a2cde58570c24c13ef3289490980961c5
https://github.com/python/cpython/commit/e4846a93ac07a8ae9aa18203af0dd13d6e7a6995
https://github.com/python/cpython/commit/f7fceed79ca1bceae8dbe5ba5bc8928564da7211
https://github.com/python/cpython/issues/143916
https://github.com/python/cpython/pull/143917
https://mail.python.org/archives/list/security-announce@python.org/thread/BJ6QPHNSHJTS3A7CFV6IBMCAP2DWRVNT/

Configurations

No configuration.

History

No history.

Information

Published : 2026-01-20 22:15

Updated : 2026-01-26 15:05

NVD link : CVE-2026-0865

Mitre link : CVE-2026-0865

CVE.ORG link : CVE-2026-0865

JSON object : View

Products Affected

No product.

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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