cbcvebase.
CVE-2026-4224
published 2026-03-16

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…

PriorityP342high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.62%
45.8th percentile
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.

Affected

18 ranges
VendorProductVersion rangeFixed in
debianpypy3< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
debianpython2.7< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
debianpython3.11< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
debianpython3.13< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
debianpython3.14< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
debianpython3.9< python3.14 3.14.3-4 (sid)python3.14 3.14.3-4 (sid)
msrcazl3_python3_3.12.9-9_on_azure_linux_3.0
msrccbl2_python3_3.9.19-19_on_cbl_mariner_2.0
pythonpython< 3.10.03.10.0
pythonpython
pythonpython>= 3.13.0 < 3.13.133.13.13
pythonpython>= 3.14.0 < 3.14.43.14.4
python_software_foundationcpython< 3.13.133.13.13
python_software_foundationcpython>= 3.14.0 < 3.14.43.14.4
python_software_foundationcpython>= 3.15.0a1 < 3.15.0a83.15.0a8
ubuntupython3.10
ubuntupython3.12
ubuntupython3.14

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.06.0MEDIUMCVSS: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
osv6.0MEDIUM
vendor_debian6.0MEDIUM
vendor_msrc6.0MEDIUM
vendor_redhat6.0MEDIUM
vendor_ubuntu3.3LOW
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