---
id: CVE-2026-34360
title: >-
  HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare
  interoperability in Java
summary: >-
  HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare
  interoperability in Java. Prior to version 6.9.4, the /loadIG HTTP endpoint in
  the FHIR Validator HTTP service accepts a user-supplied URL via JSON body and
  m…
severity: medium
cvss: 5.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N'
cwe:
  - CWE-918
vendor: hapifhir
product: hl7_fhir_core
affected:
  - hl7_fhir_core < 6.9.4
patched:
  - hl7_fhir_core 6.9.4
published: '2026-03-31'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-34360'
references:
  - url: >-
      https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3ww8-jw56-9f5h
    label: security-advisories@github.com
  - url: >-
      https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-3ww8-jw56-9f5h
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00324
epssPercentile: 0.2269
ingestedAt: '2026-07-24T20:38:02.897Z'
---

## Overview

HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.4, the /loadIG HTTP endpoint in the FHIR Validator HTTP service accepts a user-supplied URL via JSON body and makes server-side HTTP requests to it without any hostname, scheme, or domain validation. An unauthenticated attacker with network access to the validator can probe internal network services, cloud metadata endpoints, and map network topology through error-based information leakage. With explore=true (the default for this code path), each request triggers multiple outbound HTTP calls, amplifying reconnaissance capability. This issue has been patched in version 6.9.4.

## Affected

- `hl7_fhir_core < 6.9.4`

## Remediation

Upgrade past the affected range:

- `hl7_fhir_core 6.9.4`