CVE-2026-0865
wsgiref.headers.Headers allows header newline injection
- State
- Published
- Severity
- 5.9 Medium
- Published
- Jan 20, 2026
- Updated
- Mar 3, 2026
- Reserved
- Jan 12, 2026
Description
User-controlled header names and values containing newlines can allow injecting HTTP headers.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.9 Medium | CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N | PSF |
Weaknesses
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Affected Products
| Product | Versions |
|---|---|
CPythonPython Software Foundation |
|
References
- https://github.com/python/cpython/pull/143917patch
- https://github.com/python/cpython/issues/143916issue-tracking
- https://mail.python.org/archives/list/security-announce@python.org/thread/BJ6QPHNSHJTS3A7CFV6IBMCAP2DWRVNT/vendor-advisory
- https://github.com/python/cpython/commit/22e4d55285cee52bc4dbe061324e5f30bd4dee58patch
- https://github.com/python/cpython/commit/23e3c0ae867cca0130e441e776c9955b9027c510patch
- https://github.com/python/cpython/commit/4802b96a2cde58570c24c13ef3289490980961c5patch
- https://github.com/python/cpython/commit/f7fceed79ca1bceae8dbe5ba5bc8928564da7211patch
- https://github.com/python/cpython/commit/2f840249550e082dc351743f474ba56da10478d2patch
- https://github.com/python/cpython/commit/e4846a93ac07a8ae9aa18203af0dd13d6e7a6995patch
- https://github.com/python/cpython/commit/66da7bf6fe7b81e3ecc9c0a25bd47d4616c8d1a6patch
- https://github.com/python/cpython/commit/83ecd18779f286d872f68bfce175651e407d9fffpatch
- https://github.com/python/cpython/commit/bfba660085767f8c2d582134e9d511a85eda04cfpatch
- https://github.com/python/cpython/commit/286e3ac39984fe85a17f4ab39c64d382137aae5fpatch
- https://github.com/python/cpython/commit/8bb044d29310bb05d15086cdaa8bf64867d61a97patch
- https://github.com/python/cpython/commit/c592227ffb48679af9845a45dbb0875d975bb219patch
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