CVE-2026-62296

Summary

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.

Affected Software

VendorProductVersion RangeStatus
hapifhirorg.hl7.fhir.core< 6.9.11affected
hapifhirca.uhn.hapi.fhir:org.hl7.fhir.r5< 6.9.11affected
hapifhirca.uhn.hapi.fhir:org.hl7.fhir.utilities< 6.9.11affected
hapifhirca.uhn.hapi.fhir:org.hl7.fhir.validation< 6.9.11affected
hapifhirca.uhn.hapi.fhir:org.hl7.fhir.validation.cli< 6.9.11affected

Weaknesses

  • CWE-20: CWE-20: Improper Input Validation
  • CWE-400: CWE-400: Uncontrolled Resource Consumption
  • CWE-674: CWE-674: Uncontrolled Recursion

References