Name: CVE-2026-4224: Uncontrolled Recursion
Creator: Rapid7
Published: 2026-03-16T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-4224, CWE-674, CVSS 7.5, EPSS 0.00638

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 Details

CVSS 4.0 Base Score: 6 (MEDIUM)
CVSS 4.0 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 7.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alma_linux	—	Upgrade python3.14-develUpgrade python3.14-freethreading-debugUpgrade python3.12-tkinterUpgrade python3.12Upgrade python3.14-tkinterUpgrade python3.14-freethreading-develUpgrade python3.14-libsUpgrade python3.14Upgrade python3.14-idleUpgrade python3.12-libsUpgrade python3.12-debugUpgrade python3.14-freethreading-testUpgrade python3.12-idleUpgrade python3.14-freethreadingUpgrade python3.12-develUpgrade python3.14-testUpgrade python3.12-testUpgrade python3.12-rpm-macrosUpgrade python3.14-freethreading-tkinterUpgrade python3.14-freethreading-idleUpgrade python3.14-debugUpgrade python3.14-freethreading-libs	Apr 29, 2026	Apr 27, 2026
Alpine Linux	—	Upgrade python3	Jun 18, 2026	Mar 16, 2026
Amazon Linux Ami 2	—	Upgrade python-testUpgrade python3-testUpgrade python3-debugUpgrade pythonUpgrade python3-toolsUpgrade tkinterUpgrade python-libsUpgrade python-develUpgrade python-toolsUpgrade python3Upgrade python3-develUpgrade python-debugUpgrade python3-tkinterUpgrade python3-debuginfoUpgrade python3-libsUpgrade python-debuginfo	May 20, 2026	May 20, 2026
Amazon_linux_2023	—	Upgrade python3.12-tkinterUpgrade python3.13-tkinterUpgrade python3.14-freethreading-debugUpgrade python3.11-tkinterUpgrade python3.13-idleUpgrade python3.12-testUpgrade python3-testUpgrade python3.14-develUpgrade python3.11-debugsourceUpgrade python3.12Upgrade python3.14Upgrade python3.14-freethreading-tkinterUpgrade python3.14-freethreading-idleUpgrade python3.12-idleUpgrade python3.13Upgrade python3.12-debuginfoUpgrade python3.11-libsUpgrade python3.11-idleUpgrade python3.13-testUpgrade python3.13-debugUpgrade python3.13-develUpgrade python3.14-freethreading-libsUpgrade python3.14-debugsourceUpgrade python3.14-testUpgrade python3.14-freethreading-develUpgrade python3.14-freethreadingUpgrade python3.11-debuginfoUpgrade python3.9-debuginfoUpgrade python3.14-debuginfoUpgrade python3.13-debuginfoUpgrade python3.14-tkinterUpgrade python3.14-freethreading-testUpgrade python3.13-libsUpgrade python3.11-develUpgrade python3.11Upgrade python3.14-libsUpgrade python3-idleUpgrade python3.13-debugsourceUpgrade python3-libsUpgrade python3.12-libsUpgrade python3.12-debugUpgrade python3.11-testUpgrade python3.9-debugsourceUpgrade python3.11-debugUpgrade python3.14-debugUpgrade python3-tkinterUpgrade python3-develUpgrade python3-debugUpgrade python3.13-freethreading-debugUpgrade python3.13-freethreadingUpgrade python3.12-develUpgrade python3.12-debugsourceUpgrade python-unversioned-commandUpgrade python3Upgrade python3.14-idle	Apr 14, 2026	Mar 16, 2026
Debian	—	Upgrade python3.11Upgrade python3.13Upgrade python3.9	May 17, 2026	May 17, 2026
Ibm Aix	—	Apply the fix or workaround for python_advisory20	Jul 15, 2026	Jul 14, 2026
Oracle_linux	—	Upgrade python3.14-freethreading-libsUpgrade python3-tkinterUpgrade python3.14-freethreading-tkinterUpgrade python3-idleUpgrade python-unversioned-commandUpgrade python3.14-debugUpgrade python3.14-freethreadingUpgrade python3.14-freethreading-idleUpgrade python3.14-testUpgrade python3.12-rpm-macrosUpgrade python3-libsUpgrade python3.12-develUpgrade python3-develUpgrade python3.12-idleUpgrade python3.14-tkinterUpgrade python3.12Upgrade python3Upgrade python3.14-freethreading-debugUpgrade python3.14Upgrade python3.14-freethreading-develUpgrade python3.14-idleUpgrade python3.12-tkinterUpgrade python3-debugUpgrade python3.12-testUpgrade python3.14-freethreading-testUpgrade python3.14-develUpgrade python3.14-libsUpgrade python3-testUpgrade python3.12-libsUpgrade python3.12-debug	Apr 29, 2026	Mar 16, 2026
Redhat_linux	—	Upgrade python3.12No solution existsUpgrade python3.14-freethreading-tkinterUpgrade python3.12-idleUpgrade python3.12-testUpgrade python3.14-freethreading-debugUpgrade python3.12-rpm-macrosUpgrade python3.14-develUpgrade python-unversioned-commandUpgrade python3.14-debugsourceUpgrade python3-testUpgrade python3.12-tkinterUpgrade python3.14Upgrade python3.14-libsUpgrade python3.12-debugUpgrade python3Upgrade python3-idleUpgrade python3.14-idleUpgrade python3.12-debugsourceUpgrade python3.14-testUpgrade python3.14-freethreadingUpgrade python3.14-debuginfoUpgrade python3-develUpgrade python3-tkinterUpgrade python3-libsUpgrade python3-debugUpgrade python3.14-freethreading-develUpgrade python3.14-freethreading-testUpgrade python3.14-freethreading-idleUpgrade python3.12-debuginfoUpgrade python3.14-tkinterUpgrade python3.12-develUpgrade python3.14-debugUpgrade python3.14-freethreading-libsUpgrade python3.12-libs	Apr 29, 2026	Mar 16, 2026
Rocky_linux	—	Upgrade python3.12-debugUpgrade python3.12-idleUpgrade python3.14-develUpgrade python3.14-freethreading-develUpgrade python3.14-freethreading-debugUpgrade python3-libsUpgrade python3-idleUpgrade python3.14-idleUpgrade python3.14-debugUpgrade python3.12-develUpgrade python3Upgrade python3.12-testUpgrade python3.12-libsUpgrade python3.14-tkinterUpgrade python3.14-freethreading-testUpgrade python3.14-debugsourceUpgrade python3.12-debugsourceUpgrade python3.12-debuginfoUpgrade python3-testUpgrade python3.14-debuginfoUpgrade python3.14Upgrade python3.14-freethreading-tkinterUpgrade python3-develUpgrade python3.14-libsUpgrade python3.14-freethreadingUpgrade python3.12-tkinterUpgrade python3-debugUpgrade python3-tkinterUpgrade python3.14-freethreading-idleUpgrade python3.14-freethreading-libsUpgrade python3.12Upgrade python3.14-test	Apr 29, 2026	Apr 28, 2026
Suse	—	Upgrade python-baseUpgrade python313-nogilUpgrade python313-nogil-testsuiteUpgrade python313-toolsUpgrade python313Upgrade python313-base-x86-64-v3Upgrade python-docUpgrade python312-develUpgrade python39-docUpgrade python-demoUpgrade python310-testsuiteUpgrade python311-develUpgrade python3-dbmUpgrade python311-tkUpgrade libpython3_11-1_0Upgrade python3-doc-devhelpUpgrade python314-tkUpgrade libpython2_7-1_0Upgrade libpython3_14-1_0-x86-64-v3Upgrade python311-doc-devhelpUpgrade python312-doc-devhelpUpgrade libpython3_14-1_0Upgrade python3Upgrade python-idleUpgrade python311-testsuiteUpgrade python3-toolsUpgrade python312-idleUpgrade python-doc-pdfUpgrade python313-tkUpgrade libpython3_12-1_0-32bitUpgrade libpython3_13t1_0Upgrade python36-develUpgrade pythonUpgrade python310-32bitUpgrade python311-docUpgrade python-gdbmUpgrade python314-idleUpgrade python314-base-x86-64-v3Upgrade python311-32bitUpgrade libpython3_11-1_0-32bitUpgrade python39-base-32bitUpgrade python310-baseUpgrade python314-dbmUpgrade python39-cursesUpgrade python312-base-32bitUpgrade python310-docUpgrade python314-doc-devhelpUpgrade python3-develUpgrade python310-idleUpgrade python314Upgrade python39-32bitUpgrade python39-baseUpgrade python3-cursesUpgrade python313-nogil-develUpgrade python-tkUpgrade python313-nogil-dbmUpgrade python39-dbmUpgrade libpython2_7-1_0-32bitUpgrade libpython3_10-1_0Upgrade python313-idleUpgrade python-base-32bitUpgrade python314-toolsUpgrade python3-idleUpgrade python313-nogil-cursesUpgrade python310-base-32bitUpgrade python-32bitUpgrade python312-docUpgrade python311-dbmUpgrade python39-testsuiteUpgrade python312-32bitUpgrade python311-baseUpgrade libpython3_13-1_0Upgrade libpython3_4m1_0-32bitUpgrade python311-cursesUpgrade python3-docUpgrade libpython3_6m1_0-32bitUpgrade python313-nogil-toolsUpgrade python310Upgrade python313-nogil-idleUpgrade python314-x86-64-v3Upgrade python312-tkUpgrade python310-dbmUpgrade python3-baseUpgrade libpython3_9-1_0Upgrade libpython3_6m1_0Upgrade python39-doc-devhelpUpgrade python313-docUpgrade python312-toolsUpgrade python311-idleUpgrade python314-develUpgrade python314-cursesUpgrade python312Upgrade python310-cursesUpgrade python312-baseUpgrade python311-toolsUpgrade python310-toolsUpgrade python3-testsuiteUpgrade python314-baseUpgrade python313-x86-64-v3Upgrade python312-testsuiteUpgrade python312-dbmUpgrade python310-develUpgrade python36Upgrade python311Upgrade libpython3_10-1_0-32bitUpgrade python36-baseUpgrade python313-dbmUpgrade libpython3_13-1_0-x86-64-v3Upgrade python313-nogil-baseUpgrade python-xmlUpgrade libpython3_9-1_0-32bitUpgrade python312-cursesUpgrade python-develUpgrade python39-idleUpgrade python314-docUpgrade libpython3_12-1_0Upgrade python310-doc-devhelpUpgrade python39-toolsUpgrade python39-tkUpgrade python311-base-32bitUpgrade python-cursesUpgrade python39Upgrade python313-testsuiteUpgrade python313-doc-devhelpUpgrade python313-develUpgrade python313-baseUpgrade python313-nogil-tkUpgrade python313-cursesUpgrade python310-tkUpgrade python3-tkUpgrade libpython3_4m1_0Upgrade python39-devel	Apr 8, 2026	Apr 7, 2026
Ubuntu	—	Upgrade libpython3.7 (Ubuntu Pro)Upgrade python3.6 (Ubuntu Pro)Upgrade python3.10Upgrade python3.7 (Ubuntu Pro)Upgrade python3.9 (Ubuntu Pro)Upgrade libpython3.12t64Upgrade libpython2.7 (Ubuntu Pro)Upgrade libpython3.8 (Ubuntu Pro)Upgrade python3.5 (Ubuntu Pro)Upgrade libpython3.9 (Ubuntu Pro)Upgrade python2.7 (Ubuntu Pro)Upgrade python3.11 (Ubuntu Pro)Upgrade python3.14Upgrade libpython3.5 (Ubuntu Pro)Upgrade libpython3.4 (Ubuntu Pro)Upgrade python3.8 (Ubuntu Pro)Upgrade python3.4 (Ubuntu Pro)Upgrade libpython3.10Upgrade python3.12Upgrade libpython3.6 (Ubuntu Pro)Upgrade libpython3.14Upgrade libpython3.11 (Ubuntu Pro)	Jul 6, 2026	Mar 16, 2026
Vmware Photon_os	—	Use 'tdnf update' to upgrade all packages to the latest version.	May 27, 2026	Mar 16, 2026

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CVSS Details

Covered by Rapid7

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