Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:N) | No integrity impact |
| Availability (VA:N) | No availability impact |
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Hapifhir Hl7 Fhir Core
CVE-2026-55471 affects Hapifhir Hl7 Fhir Core, a product from Hapifhir. Before acting, confirm where Hapifhir Hl7 Fhir Core runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: 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.
The weakness class is XML External Entity. XML parsing can be abused to read files or reach internal systems.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Hapifhir Hl7 Fhir Core |
| Affected versions | Hl7 Fhir Core before 6.9.10 |
| Published | Jul 8, 2026 |
| Last modified | Jul 16, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Hapifhir Hl7 Fhir Core and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Hapifhir Hl7 Fhir Core named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Hapifhir Hl7 Fhir Core to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-611: XML External Entity More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
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.
HAPI FHIR is a complete implementation of the HL7 FHIR standard for healthcare interoperability in Java. Prior to version 6.9.4, ManagedWebAccessUtils.getServer() uses String.startsWith() to match request URLs against configured server URLs for authentication credential dispatch. Because configured server URLs (e.g., http://tx.fhir.org) lack a trailing slash or host boundary check, an attacker-controlled domain like http://tx.fhir.org.attacker.com matches the prefix and receives Bearer tokens, Basic auth credentials, or API keys when the HTTP client follows a redirect to that domain. This issue has been patched in version 6.9.4.
Apache CXF's EndpointReferenceUtils and W3CMultiSchemaFactory classes construct a SAXParserFactory without the necessary JAXP hardening configurations, enabling out-of-band (OOB) external entity resolution. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fix this issue.
Improper Restriction of XML External Entity Reference vulnerability in RTI Connext Professional (Core Libraries) allows Serialized Data External Linking. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.1, from 6.1.0 before 6.1.*, from 6.0.0 before 6.0.*, from 5.3.0 before 5.3.*, from 5.2.0 before 5.2.*, from 4.3x before 5.1.*.
Improper Restriction of XML External Entity Reference vulnerability in RTI Connext Professional (Recording Service,Routing Service,Queueing Service,Cloud Discovery Service,Observability Collector) allows Serialized Data External Linking, Data Serialization External Entities Blowup. This issue affects Connext Professional: from 7.4.0 before 7.7.0, from 7.0.0 before 7.3.1.1, from 6.1.0 before 6.1.2.34, from 6.0.0 before 6.0.*, from 5.3.0 before 5.3.*.
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, Crawler::addXmlContent() set DOMDocument::$validateOnParse = true before loadXML(), re-enabling external entity resolution and allowing attacker-supplied XML to expand file:// entities such as local files. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
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