CVE-2026-55471 HIGH

CVE-2026-55471: HAPI FHIR: XXE in XsltUtilities.saxonTransform via unhardened Saxon TransformerFactory

Vendor Hapifhir
Product org.hl7.fhir.core
Weakness CWE-611 · XXE
Published July 8, 2026
Last update July 9, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N

What the vulnerability does

01Description

HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to 6.9.10, org.hl7.fhir.utilities.XsltUtilities saxonTransform(...) overloads instantiated a bare net.sf.saxon.TransformerFactoryImpl() without ACCESS_EXTERNAL_DTD or ACCESS_EXTERNAL_STYLESHEET restrictions, allowing an attacker who controls or can tamper with transformed XML to trigger XML External Entity injection for local file disclosure and blind XXE or SSRF to arbitrary URLs reachable from the host. This issue is fixed in version 6.9.10.

Key dates

02Disclosure timeline

July 8, 2026 CVE published
July 9, 2026 Record updated

Related vulnerabilities

04Related CVE