Resource exhaustion in Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.r5
CVE-2026-62296
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (42.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.r5 — versions < 6.9.11
- Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.utilities — versions < 6.9.11
- Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.validation — versions < 6.9.11
- Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.validation.cli — versions < 6.9.11
- Hapifhir Org.hl7.fhir.core — versions < 6.9.11
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-62296?
- CVE-2026-62296 is a high-severity vulnerability in Hapifhir Ca.uhn.hapi.fhir:org.hl7.fhir.r5, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-08-07.
- How severe is CVE-2026-62296?
- High severity. CVSS v3 base score is 7.5 out of 10.