CVE-2026-88789
HIGH 8.6Improper 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.
Severe if exploited (CVSS 8.6), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.5%chance of exploitation in 30 days · 43rd percentile
Impact if exploited
8.6CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityNone
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-88789/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-88789/poc.json
Weakness (CWE)
- CWE-611: Improper restriction of XML external entity reference
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
All CVSS metrics
- HIGH 8.6 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N - HIGH 8.6 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N