Skip to content
Fencer Intel
critical 9.3

CVE-2026-34361 json

HAPI FHIR: Unauthenticated SSRF via /loadIG Chains with startsWith() Credential Leak for Authentication Token Theft

published 7mo ago modified 3mo ago also EUVD-2026-17528 , GHSA-vr79-8m62-wh98

cvss
9.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits
0
none known

Summary

HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.4, the FHIR Validator HTTP service exposes an unauthenticated "/loadIG" endpoint that makes outbound HTTP requests to attacker-controlled URLs. Combined with a startsWith() URL prefix matching flaw in the credential provider (ManagedWebAccessUtils.getServer()), an attacker can steal authentication tokens (Bearer, Basic, API keys) configured for legitimate FHIR servers by registering a domain that prefix-matches a configured server URL. This issue has been patched in version 6.9.4.

Patch / fix

  • maven ca.uhn.hapi.fhir:org.hl7.fhir.validation 6.9.4
  • ca.uhn.hapi.fhir org.hl7.fhir.validation 6.9.4
  • hapifhir hl7_fhir_core 6.9.4

Is CVE-2026-34361 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
7mo ago

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-vr79-8m62-wh98 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 9.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
GitHub 3.1 9.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
NVD 3.1 9.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

Affected packages

ecosystem package affected fixed in
maven ca.uhn.hapi.fhir:org.hl7.fhir.validation
<6.9.4
6.9.4

Affected products

  • hapifhir org.hl7.fhir.core

Classification

Weakness
  • CWE-552 Files or Directories Accessible to External Parties
  • CWE-522 Insufficiently Protected Credentials

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.