Apache Camel Quarkus: Improper Restriction of XML External Entity Reference
CVE-2026-88789 is a high-severity improper restriction of XML external entity reference vulnerability in Apache Camel Quarkus from Apache, 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. The record lists versions 3.33.3, 3.40.0 as the first without the flaw, so updating Apache Camel Quarkus to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.41% 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
- Update Apache Camel Quarkus to 3.33.3 or 3.40.0, whichever matches your release line, or a later version.
- 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 |
|---|---|---|---|
| Apache | Apache Camel Quarkus | 3.2.0 up to, but not including, 3.33.3; 3.34.0 up to, but not including, 3.40.0 | 3.33.3, 3.40.0 |
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 (apache.org).
Official description
Improper Restriction of XML External Entity Reference in the XSLT support extension (camel-quarkus-support-xalan) in Apache Camel Quarkus from 3.2.0 before 3.33.3 and from 3.34.0 before 3.40.0 on all platforms allows an attacker who supplies the XML document being transformed to read local files or issue requests to internal network locations via an external entity declaration in that document. The extension supplies its own Xalan-backed TransformerFactory to the xslt component and registers it as the JAXP default. Xalan-J 2.7.x predates JAXP 1.5 and does not honour javax.xml.XMLConstants.ACCESS_EXTERNAL_DTD or ACCESS_EXTERNAL_STYLESHEET, so the external access restrictions Apache Camel applies to the TransformerFactory it creates were not in effect. On the xslt component path this affects message bodies that reach the transformer already as a javax.xml.transform.Source; bodies of other types are converted to a SAXSource by Apache Camel with external entities and external DTD loading disabled, and are not affected. Because the factory is also the JAXP default, other code in the application obtaining one through TransformerFactory.newInstance() loses the same restrictions without error. Applications are affected if they use any of camel-quarkus-xslt, camel-quarkus-xslt-saxon, camel-quarkus-tika or camel-quarkus-xmlsecurity, each of which brings the XSLT support extension onto the classpath. For all but camel-quarkus-xslt, the exposure is limited to the JAXP default factory, since those extensions do not perform XSLT transformations themselves. Users are recommended to upgrade to version 3.33.3 or 3.40.0, which fixes this issue.
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: no, technical impact: partial).
References
Patches and release notes
Other references
Recent Improper Restriction of XML External Entity Reference vulnerabilities
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