CVE-2026-62296: CWE-20: Improper Input Validation in hapifhir org.hl7.fhir.core
HAPI FHIR versions prior to 6.9.11 contain an improper input validation vulnerability in the XhtmlParser component. Specifically, the parser does not limit the maximum element nesting depth in text.div narratives, which can cause unbounded recursion and lead to a StackOverflowError. This can crash parsing or validation threads processing attacker-supplied FHIR JSON or XML resources. The issue is fixed in version 6.9.11.
AI Analysis
Technical Summary
The vulnerability in HAPI FHIR's org.hl7.fhir.core library involves improper input validation where the XhtmlParser.java class does not impose a maximum element nesting depth. This allows an attacker to craft deeply nested text.div narratives that trigger unbounded recursion between parseElementInner() and parseElement(), causing a StackOverflowError. This denial-of-service condition affects validator services and any application parsing attacker-controlled FHIR resources. The flaw is addressed in version 6.9.11.
Potential Impact
An attacker capable of submitting malicious FHIR resources with deeply nested narratives can cause a denial-of-service by crashing parsing or validation threads due to stack overflow. This impacts availability of services relying on the vulnerable parser but does not affect confidentiality or integrity.
Mitigation Recommendations
A fix is available in HAPI FHIR version 6.9.11. Users should upgrade to version 6.9.11 or later to remediate this vulnerability. No other mitigation guidance is provided.
CVE-2026-62296: CWE-20: Improper Input Validation in hapifhir org.hl7.fhir.core
Description
HAPI FHIR versions prior to 6.9.11 contain an improper input validation vulnerability in the XhtmlParser component. Specifically, the parser does not limit the maximum element nesting depth in text.div narratives, which can cause unbounded recursion and lead to a StackOverflowError. This can crash parsing or validation threads processing attacker-supplied FHIR JSON or XML resources. The issue is fixed in version 6.9.11.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in HAPI FHIR's org.hl7.fhir.core library involves improper input validation where the XhtmlParser.java class does not impose a maximum element nesting depth. This allows an attacker to craft deeply nested text.div narratives that trigger unbounded recursion between parseElementInner() and parseElement(), causing a StackOverflowError. This denial-of-service condition affects validator services and any application parsing attacker-controlled FHIR resources. The flaw is addressed in version 6.9.11.
Potential Impact
An attacker capable of submitting malicious FHIR resources with deeply nested narratives can cause a denial-of-service by crashing parsing or validation threads due to stack overflow. This impacts availability of services relying on the vulnerable parser but does not affect confidentiality or integrity.
Mitigation Recommendations
A fix is available in HAPI FHIR version 6.9.11. Users should upgrade to version 6.9.11 or later to remediate this vulnerability. No other mitigation guidance is provided.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-13T18:37:08.488Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a772657bf8831d539846b9a
Added to database: 08/08/2026, 12:51:35 UTC
Last enriched: 08/08/2026, 12:52:25 UTC
Last updated: 08/08/2026, 15:06:11 UTC
Views: 5
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