{"cve":"CVE-2026-4224","nvd":{"published":"2026-03-16T18:16:10.070","modified":"2026-08-13T01:16:53.273","status":"Modified","description":"When an Expat parser with a registered ElementDeclHandler parses an inline\ndocument type definition containing a deeply nested content model a C stack\noverflow occurs.","cvss_v4":{"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","score":6.0},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-674"],"references":["https://github.com/python/cpython/commit/196edfb06a7458377d4d0f4b3cd41724c1f3bd4a","https://github.com/python/cpython/commit/24ce88b285f56ee11626cf5e472af3cd8cc7c621","https://github.com/python/cpython/commit/642865ddf4b232da1f3b1f7abcfa3254c4bfe785","https://github.com/python/cpython/commit/af856a7177326ac25d9f66cc6dd28b554d914fee","https://github.com/python/cpython/commit/e0a8a6da90597a924b300debe045cdb4628ee1f3"],"products":["python:python"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-4224","score":0.00702,"percentile":0.53264,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}