Apache Camel: Improper Restriction of XML External Entity Reference
CVE-2026-90885 is a high-severity improper restriction of XML external entity reference vulnerability in Apache Camel from Apache, with a CVSS 3.1 base score of 7.5 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 4.18.5, 4.22.2 as the first without the flaw, so updating Apache Camel to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.6% 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 to 4.18.5 or 4.22.2, 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 | 4.0.0 up to, but not including, 4.18.5; 4.19.0 up to, but not including, 4.22.2 | 4.18.5, 4.22.2 |
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
- UnchangedImpact stays within the vulnerable component.
- 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:U/C:H/I:N/A:N. Scored by CNA (apache.org).
Official description
Improper Restriction of XML External Entity Reference vulnerability in Apache Camel Saxon component. This issue affects Apache Camel: from 4.0.0 before 4.18.5, from 4.19.0 before 4.22.2. XQueryBuilder in camel-saxon, which evaluates expressions for the xquery language and the xquery component, built its default Saxon Configuration with parse options that set only a whitespace stripping rule, leaving the XML parser at its defaults, under which a DOCTYPE declaration is accepted and external entities are resolved. A message body of type String or byte[], or any body read as an InputStream, is first turned into a javax.xml.transform.Source by Camel's own XML type converters, which configure the parser against external entities, so those bodies were not affected. A body that was already a Source, however, was handed to Saxon unchanged, and when that Source still had to be parsed, as a stream-based Source does, Saxon parsed it with that Configuration, bypassing the protection applied to the other body types. Such a body arises, for example, after a route converts the message with convertBodyTo(Source.class), or when a component or processor earlier in the route sets the body to a stream-based Source. A DOCTYPE with an external subset, or an external entity, declared in that body was therefore resolved and expanded into the document the expression was evaluated against. An external sender whose XML reaches an XQuery expression or an xquery endpoint in that form could read files readable by the Camel process and cause the process to issue requests to hosts the document names. No non-default option is required, since the default Configuration is used whenever the route does not supply one of its own. Users are recommended to upgrade to version 4.23.0, which fixes the issue. If users are on the 4.22.x releases stream, then they are suggested to upgrade to 4.22.2. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.5. The 4.14.x releases stream and earlier, as well as the 4.15.x to 4.17.x and 4.19.x to 4.21.x release lines, reached end of life before this issue was resolved and will not receive a fix, so deployments on them must move to a supported release. For deployments that cannot upgrade immediately, do not evaluate XQuery over a message body that is already a javax.xml.transform.Source when that body carries XML from an untrusted sender, or set the configuration option of the xquery endpoint or language to a Saxon Configuration whose parse options refuse a DOCTYPE declaration and disable external entities and external DTD loading, which is what the fixed releases now apply by default.
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).
References
Patches and release notes
Other references
Other vulnerabilities in Apache Camel
- 8.8 High severity
- 8.2 High severity
- 7.5 High severity
- 7.5 High severity
- 8.8 High severity
- 8.2 High severity
Recent Improper Restriction of XML External Entity Reference vulnerabilities
- 8.7 High severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
- 7.1 High severity
- 8.2 High severity
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