CVE-2026-4224

When an Expat parser with a registered ElementDeclHandler parses an inline document type definition containing a deeply nested content model a C stack overflow occurs.

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 NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a	Patch
https://github.com/python/cpython/commit/24ce88b285f56ee11626cf5e472af3cd8cc7c621
https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785	Patch
https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee	Patch
https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3	Patch
https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768	Patch
https://github.com/python/cpython/issues/145986	Issue Tracking
https://github.com/python/cpython/pull/145987	Patch
https://mail.python.org/archives/list/security-announce@python.org/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/	Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/03/16/4	Mailing List 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::::::::
	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-2026-4224

Mitre link : CVE-2026-4224

CVE.ORG link : CVE-2026-4224

JSON object : View

Products Affected

python

python

CWE

CWE-674

Uncontrolled Recursion

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