fhir-ig-publisher: Improper Restriction of XML External Entity Reference
CVE-2024-52807 is a high-severity improper restriction of XML external entity reference vulnerability in fhir-ig-publisher from HL7, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected fhir-ig-publisher versions: < 1.7.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.57% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of fhir-ig-publisher you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| HL7 | fhir-ig-publisher | < 1.7.4 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N. Scored by CNA (github.com).
Official description
The HL7 FHIR IG publisher is a tool to take a set of inputs and create a standard FHIR IG. Prior to version 1.7.4, XSLT transforms performed by various components are vulnerable to XML external entity injections. A processed XML file with a malicious DTD tag `( ]>` could produce XML containing data from the host system. This impacts use cases where org.hl7.fhir.publisher is being used to within a host where external clients can submit XML. A previous release provided an incomplete solution revealed by new testing. This issue has been patched as of version 1.7.4. No known workarounds are available.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Restriction of XML External Entity Reference
The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.
How developers prevent this class of flaw
- Many XML parsers and validators can be configured to disable external entity expansion.
More Improper Restriction of XML External Entity Reference vulnerabilities (CWE-611)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Other vulnerabilities in fhir-ig-publisher
- 8.1 High severity
Recent Improper Restriction of XML External Entity Reference vulnerabilities
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.1 High severity
- 7.2 High severity
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