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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
hapifhir org.hl7.fhir.core affected
Version Status Constraints
< 6.9.11 affected —
hapifhir ca.uhn.hapi.fhir:org.hl7.fhir.r5 affected
Version Status Constraints
< 6.9.11 affected —
hapifhir ca.uhn.hapi.fhir:org.hl7.fhir.utilities affected
Version Status Constraints
< 6.9.11 affected —
hapifhir ca.uhn.hapi.fhir:org.hl7.fhir.validation affected
Version Status Constraints
< 6.9.11 affected —
hapifhir ca.uhn.hapi.fhir:org.hl7.fhir.validation.cli affected
Version Status Constraints
< 6.9.11 affected —

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Project Subscriptions

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/hapifhir/org.hl7.fhir.core/commit/396f447500407693d6ae1e64db59782862ca7506 cve-icon
https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-5v24-q6x8-hc38 cve-icon
History

Fri, 07 Aug 2026 20:15:00 +0000

Type Values Removed Values Added
Description 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.
Title HAPI FHIR: XHTML narrative parser unbounded recursion causes StackOverflow denial of service
Weaknesses CWE-20
CWE-400
CWE-674
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-07T20:03:17.024Z

Reserved: 2026-07-13T18:37:08.488Z

Link: CVE-2026-62296

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-07T21:30:18Z

Weaknesses