Description
Apache XmlSchema doesn't limit how deeply schema structures can be nested when it builds its schema model, so a malicious schema can make parsing recurse until the stack overflows. This causes 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/9z1vg8wmvwpfw748fb2nb55w4hgbnxol Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/09/29/16 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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