CVE-2026-55470 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-55470HIGH

hapifhir org.hl7.fhir.core — HAPI FHIR: DSTU2 FHIRPathEngine.matches() missing RegexTimeout protection allows ReDoS

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .0044   37.2     —

AFFECTED
  Product            Versions    Fixed
  org.hl7.fhir.core  < 6.9.10 –  —

TIMELINE
  Jun 16  Reserved by GitHub_M
  Jul 8   EXPLOIT PUBLISHED — CVE-2026-55470 (hapifhir org.hl7.fhir.core). Public exploit reference added.
  Jul 8   Published (CNA: GitHub_M)

CWE-1333 · CNA: GitHub_M · CVSS v3.1 · 3 references · NVD status: Analyzed

Description

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
June 16, 2026	Reserved	Reserved by GitHub_M
July 8, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-55470 (hapifhir org.hl7.fhir.core). Public exploit reference added.
July 8, 2026	Published	Published (CNA: GitHub_M)

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
hapifhir	org.hl7.fhir.core	—	< 6.9.10	—

Weaknesses

CWE-1333

References (3)

https://github.com/hapifhir/org.hl7.fhir.core/commit/56376f7986222626af061ca7fc27ee1ab030e590 [Patch]
https://github.com/hapifhir/org.hl7.fhir.core/releases/tag/6.9.10 [Release Notes]
https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-fxj4-p9xp-37v5 [Exploit, Third Party Advisory]

Authoritative record: CVE-2026-55470 at cve.org

Vendors: hapifhir

Weaknesses: CWE-1333

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-55470 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.