High 7.5HealthcarePublished Jul 8, 2026

CVE-2026-55470HAPI FHIR: DSTU2 FHIRPathEngine.matches() missing RegexTimeout protection allows ReDoS

Updated under an hour ago (2026-10-19 09:10 UTC)

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It affects hapifhir org.hl7.fhir.core and 1 other product. Add what you run to find out whether that includes you.

EPSS puts the chance of exploitation in the next 30 days at 0.68%, higher than 51% of scored CVEs.

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Every CVE for hapifhir org.hl7.fhir.core

Exploited in the last 30 days

HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to 6.9.10, the fix for CVE-2026-45367 incompletely patched the DSTU2 module, leaving FHIRPathEngine.matches() in org.hl7.fhir.dstu2/utils/FHIRPathEngine.java to call raw String.matches(sw) without RegexTimeout protection while replaceMatches() was updated, allowing an unauthenticated attacker to trigger catastrophic regex backtracking and exhaust server CPU. This issue is fixed in version 6.9.10.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-1333
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): 0.68% (percentile 51)
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 9, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

hapifhir org.hl7.fhir.core hapifhir:org.hl7.fhir.core (from the name)	before 6.9.10	CNA record
hapifhir hl7_fhir_core hapifhir:hl7_fhir_core	before 6.9.10	NVD

References

https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-fxj4-p9xp-37v5x-refsource-confirm, exploit, third-party-advisory
https://github.com/hapifhir/org.hl7.fhir.core/commit/56376f7986222626af061ca7fc27ee1ab030e590x-refsource-misc, patch
https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.10x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.