All vulnerabilities
CVE-2026-102496

Apache XMLSchema: Denial of service through deeply nested schema structures

Apache Software Foundation Apache XMLSchema
Open in ThreatlineRecord JSON
CVSS
7.5High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.53%Chance of exploitation activity in the next 30 days, higher than 43% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in2.3.3Fixed versionCVE List
Published29 Sep 2026Updated 29 Sep 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

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.

Text from CVE List

Affected versions 1

  • Apache XMLSchemaaffected: all versions before 2.3.3CVE List

References 1