---
title: "CVE-2026-33180: HAPI FHIR HTTP authentication leak in redirects"
url: https://erroneo.us/security/cve/CVE-2026-33180/
description: "CVE-2026-33180 (ca.uhn.hapi.fhir:org.hl7.fhir.utilities (Maven)): HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-20
date_modified: 2026-07-15
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-33180"
kev: false
cvss: 7.5
epss: 0.00491
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-33180: HAPI FHIR HTTP authentication leak in redirects

**Signal:** Normal patch cycle. No exploitation signal; fix it in your next routine update if you are affected. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.5% , percentile 41: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 41% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes ca.uhn.hapi.fhir:org.hl7.fhir.utilities (Maven) < 6.9.0, fixed in 6.9.0 ; ca.uhn.hapi.fhir:org.hl7.fhir.convertors (Maven) < 6.9.0, fixed in 6.9.0 ; ca.uhn.hapi.fhir:org.hl7.fhir.dstu2 (Maven) < 6.9.0, fixed in 6.9.0 ; ca.uhn.hapi.fhir:org.hl7.fhir.dstu3 (Maven) < 6.9.0, fixed in 6.9.0 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.utilities` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.convertors` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.dstu2` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.dstu3` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.dstu3.support` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.dstu2016may` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.model` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.r4` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.r4b` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.r5` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.validation` < 6.9.0 → fixed: 6.9.0
- Maven `ca.uhn.hapi.fhir:org.hl7.fhir.validation.cli` < 6.9.0 → fixed: 6.9.0

## Affected products (CVE record)

- hapifhir org.hl7.fhir.core: < 6.9.0

## Severity

- GitHub_M CVSS 3.1: 7.5 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`
- redhat-SADP CVSS 3.1: 8.2 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.49% probability of exploitation activity in the next 30 days; percentile 41.

## Sources

- [GitHub Advisory GHSA-p7m9-v2cm-2h7m](https://github.com/advisories/GHSA-p7m9-v2cm-2h7m)
- [CVE.org record CVE-2026-33180](https://www.cve.org/CVERecord?id=CVE-2026-33180)
- [NVD entry CVE-2026-33180](https://nvd.nist.gov/vuln/detail/CVE-2026-33180)
- [github.com](https://github.com/hapifhir/org.hl7.fhir.core/security/advisories/GHSA-p7m9-v2cm-2h7m)
- [access.redhat.com](https://access.redhat.com/security/cve/CVE-2026-33180)
- [RHBZ#2449841](https://bugzilla.redhat.com/show_bug.cgi?id=2449841)
- [security.access.redhat.com](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33180.json)

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Source page: https://erroneo.us/security/cve/CVE-2026-33180/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt