CVE-2026-3644

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

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4
https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd
https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd
https://github.com/python/cpython/issues/145599
https://github.com/python/cpython/pull/145600
https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/

Configurations

No configuration.

History

16 Mar 2026, 19:16

Type	Values Removed	Values Added
CWE		CWE-20 CWE-116

16 Mar 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-16 18:16

Updated : 2026-03-17 14:20

NVD link : CVE-2026-3644

Mitre link : CVE-2026-3644

CVE.ORG link : CVE-2026-3644

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-116

Improper Encoding or Escaping of Output

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