Expat · Expat · CVE-2026-4224
**Name of the Vulnerable Software and Affected Versions**
Expat (affected versions not specified)
**Description**
The Expat parser, when used with a registered ElementDeclHandler, is susceptible to a C stack overflow when processing an inline document type definition with a deeply nested content model. This occurs during the parsing of XML documents containing complex and deeply nested DTD content models.
**Recommendations**
At the moment, there is no information about a newer version that contains a fix for this vulnerability.