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CVE-2026-4224 Detail

Description

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  Python Software Foundation
CVSS-B 6.0 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/03/16/4 CVE
https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a Python Software Foundation
https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3 Python Software Foundation
https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768 Python Software Foundation
https://github.com/python/cpython/issues/145986 Python Software Foundation
https://github.com/python/cpython/pull/145987 Python Software Foundation
https://mail.python.org/archives/list/[email protected]/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/ Python Software Foundation

Weakness Enumeration

CWE-ID CWE Name Source
CWE-674 Uncontrolled Recursion CISA-ADP  

Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-4224
NVD Published Date:
03/16/2026
NVD Last Modified:
03/16/2026
Source:
Python Software Foundation