Vulnerability · Published Mar 31, 2026 · Assigned by GitHub_M
CVE-2026-34360HAPI FHIR: Unauthenticated Blind SSRF via /loadIG Endpoint Enables Internal Network Probing
Medium 5.8
In plain English
A medium-severity server-side request forgery in org.hl7.fhir.core from hapifhir. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | ca.uhn.hapi.fhir:org.hl7.fhir.core | 6.9.4 | GHSA-3ww8-jw56-9f5h |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| hapifhir | org.hl7.fhir.core | < 6.9.4 |
Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N