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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/python/cpython/commit/3974092b037f9a3b000fb15b48ea61ce3b25d330
https://github.com/python/cpython/commit/556aa098e738b127c714866f819b4abe2f7593d8
https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4	Patch
https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd	Patch
https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd	Patch
https://github.com/python/cpython/commit/dae4b1a21f8df4570e30986affd61bbe4ade4cef
https://github.com/python/cpython/issues/145599	Issue Tracking
https://github.com/python/cpython/pull/145600	Patch
https://mail.python.org/archives/list/security-announce@python.org/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:python:python::::::::
	cpe:2.3:a:python:python::::::::
	cpe:2.3:a:python:python:3.15.0:alpha1::::::
	cpe:2.3:a:python:python:3.15.0:alpha2::::::
	cpe:2.3:a:python:python:3.15.0:alpha3::::::
	cpe:2.3:a:python:python:3.15.0:alpha4::::::
	cpe:2.3:a:python:python:3.15.0:alpha5::::::
	cpe:2.3:a:python:python:3.15.0:alpha6::::::
	cpe:2.3:a:python:python:3.15.0:alpha7::::::

History

No history.

Information

Published : 2026-03-16 18:16

Updated : 2026-08-13 01:16

NVD link : CVE-2026-3644

Mitre link : CVE-2026-3644

CVE.ORG link : CVE-2026-3644

JSON object : View

Products Affected

python

python

CWE

CWE-20

Improper Input Validation

CWE-116

Improper Encoding or Escaping of Output

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