CVE-2026-34361
HAPI FHIR, a Java library for healthcare data, had a flaw that let attackers trick its validator service into contacting malicious URLs. This could expose authentication tokens used by legitimate FHIR servers. The problem was fixed in version 6.9.4.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
HAPI FHIR (hl7_fhir_core) versions earlier than 6.9.4, used in Java healthcare applications.
Real-world impact
An attacker could register a domain that matches a legitimate server’s URL prefix, causing the validator to send requests to the attacker’s site and steal bearer, basic, or API key tokens. This would give the attacker unauthorized access to protected FHIR resources.
Why this severity
The CVSS score of 9.3 reflects that the vulnerability is exploitable over the network without authentication, has a high confidentiality impact (tokens can be stolen), and is easy to exploit. The lack of required user interaction and the potential for credential theft make it critical.
What to do about it
- 01Upgrade HAPI FHIR to version 6.9.4 or later.
- 02Restart the HAPI FHIR service to apply the update.
NVD-referenced vendor advisory
Timeline
- Mar 31, 2026 · Mar 31, 2026PublishedDisclosed and added to the National Vulnerability Database.
- Jul 24, 2026 · 12d agoAdvisory updatedThe NVD record was last revised.
- Jul 26, 2026 · 10d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.
How it’s attacked
References & advisories
- github.com/hapifhir/org.hl7.fhir.core/…exploitvendor advisory