CVE-2026-62296 (GCVE-0-2026-62296)
Vulnerability from cvelistv5 – Published: 2026-08-07 20:03 – Updated: 2026-08-10 13:29
VLAI
EPSS
VEX
Title
HAPI FHIR: XHTML narrative parser unbounded recursion causes StackOverflow denial of service
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.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-10 13:29 UTC
CWE
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/hapifhir/org.hl7.fhir.core/sec… | x_refsource_CONFIRM |
| https://github.com/hapifhir/org.hl7.fhir.core/com… | x_refsource_MISC |
Impacted products
5 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| hapifhir | org.hl7.fhir.core |
Affected:
< 6.9.11
|
guessed | |
| hapifhir | ca.uhn.hapi.fhir:org.hl7.fhir.r5 |
Affected:
< 6.9.11
|
guessed | |
| hapifhir | ca.uhn.hapi.fhir:org.hl7.fhir.utilities |
Affected:
< 6.9.11
|
guessed | |
| hapifhir | ca.uhn.hapi.fhir:org.hl7.fhir.validation |
Affected:
< 6.9.11
|
guessed | |
| hapifhir | ca.uhn.hapi.fhir:org.hl7.fhir.validation.cli |
Affected:
< 6.9.11
|
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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