CVE-2026-3644
Incomplete control character validation in http.cookies
- State
- Published
- Severity
- 6.0 Medium
- Published
- Mar 16, 2026
- Updated
- Aug 13, 2026
- Reserved
- Mar 6, 2026
Description
The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.0 Medium | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N | PSF |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
CPythonPython Software Foundation |
|
References
- https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/vendor-advisory
- https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4patch
- https://github.com/python/cpython/issues/145599issue-tracking
- https://github.com/python/cpython/pull/145600patch
- https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590ddpatch
- https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979ddpatch
- https://github.com/python/cpython/commit/556aa098e738b127c714866f819b4abe2f7593d8patch
- https://github.com/python/cpython/commit/dae4b1a21f8df4570e30986affd61bbe4ade4cefpatch
- https://github.com/python/cpython/commit/3974092b037f9a3b000fb15b48ea61ce3b25d330patch
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