Description
The Apache XmlSchema walker (xmlschema-walker) doesn't detect cycles in type derivation, substitution groups, model groups or attribute groups. A malicious schema with such a cycle can make the walker recurse until the stack overflows, causing a denial of service. Users are recommended to upgrade to version 2.3.3, which fixes this issue.
Affected products
apache: xmlschema
References2
- lists.apache.org/thread/1cj02tobjyhjqq723bvg78yxkqt1lk7k Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/09/29/17 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 45 · as of 9 November 2026
- CWE
- CWE-674
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