HAPI-FHIR <6.9.0: Header Leak on Redirect (Java)
CVE-2026-33180 Published on March 20, 2026
HAPI FHIR HTTP authentication leak in redirects
HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.0, when setting headers in HTTP requests, the internal HTTP client sends headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP response code is returned, to the host mentioned in URL in the Location: response header value. Sending the same set of headers to subsequent hosts is a problem as this header often contains privacy sensitive information or data that could allow others to impersonate the client's request. This issue has been patched in release 6.9.0. No known workarounds are available.
Vulnerability Analysis
CVE-2026-33180 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity and availability.
Weakness Type
What is an Information Disclosure Vulnerability?
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CVE-2026-33180 has been classified to as an Information Disclosure vulnerability or weakness.
Affected Versions
hapifhir org.hl7.fhir.core Version < 6.9.0 is affected by CVE-2026-33180Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.