Vulnerability 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().
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Python | Python | < 3.13.13 |
Related Weaknesses (CWE)
References
- https://github.com/python/cpython/commit/3974092b037f9a3b000fb15b48ea61ce3b25d33
- https://github.com/python/cpython/commit/556aa098e738b127c714866f819b4abe2f7593d
- https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6bPatch
- https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dPatch
- https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dPatch
- https://github.com/python/cpython/commit/dae4b1a21f8df4570e30986affd61bbe4ade4ce
- https://github.com/python/cpython/issues/145599Issue Tracking
- https://github.com/python/cpython/pull/145600Patch
- https://mail.python.org/archives/list/[email protected]/thread/H6CADMThird Party Advisory
FAQ
What is CVE-2026-3644?
CVE-2026-3644 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 character...
How severe is CVE-2026-3644?
CVE-2026-3644 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-3644?
Check the references section above for vendor advisories and patch information. Affected products include: Python Python.