Detections
Analytics

CVE-2026-4224

medium

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.

References

https://mail.python.org/archives/list/[email protected]/thread/5M7CGUW3XBRY7II4DK43KF7NQQ3TPZ6R/

https://github.com/python/cpython/pull/145987

https://github.com/python/cpython/issues/145986

https://github.com/python/cpython/commit/eb0e8be3a7e11b87d198a2c3af1ed0eccf532768

https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3

https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee

https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785

https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a

http://www.openwall.com/lists/oss-security/2026/03/16/4

Details

Source: Mitre, NVD

Published: 2026-03-16

Updated: 2026-04-08

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 6

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

Severity: Medium

EPSS

EPSS: 0.00017