CVE-2026-62296highCWE-20CWE-400CWE-674

CVE-2026-62296: high-severity vulnerability in hapifhir ca.uhn.hapi.fhir:org.hl7.fhir.r5

HAPI FHIR: XHTML narrative parser unbounded recursion causes StackOverflow denial of service

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.5%
HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to 6.9.11, XhtmlParser.java imposes no maximum element nesting depth, so a deeply nested text.div narrative triggers unbounded recursion between parseElementInner() and parseElement(), raising a StackOverflowError. An attacker who can submit FHIR resources containing such narratives can thus crash a parsing or validation worker thread, affecting validator services and any application that parses attacker-supplied FHIR JSON or XML. This issue is fixed in version 6.9.11.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
hapifhir · ca.uhn.hapi.fhir:org.hl7.fhir.r5hapifhir · ca.uhn.hapi.fhir:org.hl7.fhir.utilitieshapifhir · ca.uhn.hapi.fhir:org.hl7.fhir.validationhapifhir · ca.uhn.hapi.fhir:org.hl7.fhir.validation.clihapifhir · org.hl7.fhir.core
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CVE-2026-62295HIGHHAPI FHIR: JSON utility parser unbounded recursion causes StackOverflow denial of serviceEPSS 0.5%CVE-2026-62293MEDIUMHAPI FHIR: Stored XSS in scan report via unescaped IG and profile titlesEPSS 0.2%