CyberSecBulletin
CVE-2026-88901NVD status: Undergoing Analysis

Apache Camel: Improper Restriction of XML External Entity Reference

Published Updated By the CyberSecBulletin desk

CVE-2026-88901 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 8.2 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, 4.22.1 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 0.45% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache Camel to 4.18.5 or 4.22.1, whichever matches your release line, or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Camel4.7.0 up to, but not including, 4.18.5; 4.19.0 up to, but not including, 4.22.14.18.5, 4.22.1

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
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:L. Scored by CNA (apache.org).

Official description

Improper Restriction of XML External Entity Reference vulnerability in Apache Camel. This issue affects Apache Camel: from 4.7.0 before 4.18.5, from 4.19.0 before 4.22.1. Improper Restriction of XML External Entity Reference in the Smooks component (camel-smooks) in Apache Camel allows an attacker who supplies the XML message body to read local files or issue requests to internal network locations via an external entity declaration in that body. This issue affects Apache Camel: from 4.7.0 before 4.18.5, from 4.19.0 before 4.22.1. The Smooks data format (.unmarshal().smooks(...)) and the Smooks component (smooks:) parse the incoming XML body with the reader Smooks resolves by default, which is the Woodstox SAX parser. That reader resolves external general and parameter entities and loads external DTDs, and camel-smooks applied none of the parser hardening that the other Camel XML components apply. A DOCTYPE with an external subset, or an external general entity, declared in the XML document is therefore resolved and expanded while the body is unmarshalled, and the resolved content is bound into the unmarshalled result and returned on InOut routes. An external sender whose XML reaches a camel-smooks data format or endpoint could therefore 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 resolving external entities was the default behaviour. Configurations that declare their own reader - EDI, CSV, JSON, or a custom reader - do not use the XML reader and are not affected. Users are recommended to upgrade to version 4.18.5, 4.22.1 or 4.23.0, which fixes the issue. Upgrade to Apache Camel 4.23.0, which fixes the issue. Users on the 4.18.x LTS releases stream should upgrade to 4.18.5. Users on the 4.22.x LTS releases stream should upgrade to 4.22.1. camel-smooks now parses the XML body with a javax.xml.parsers.DocumentBuilder that does not resolve external general or parameter entities and does not load external DTDs, and hands Smooks the resulting document, matching the secure XML processing configuration used by org.apache.camel.converter.jaxp.XmlConverter and the other Camel XML components. This hardening is applied only when the Smooks configuration parses XML with its default reader, so EDI, CSV, JSON and custom-reader configurations, and the marshalling direction, are unchanged. A new allowExternalEntities option, disabled by default, restores the previous behaviour for trusted legacy configurations that rely on external entity resolution. The camel-4.14.x releases stream and earlier reached end of life before this issue was resolved and will not receive a fix, so deployments on those lines must move to a supported release. For deployments that cannot upgrade immediately, do not apply camel-smooks to XML received from untrusted senders.

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

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).

References

Other vulnerabilities in Apache Camel

All Apache Camel vulnerabilities

Recent Improper Restriction of XML External Entity Reference vulnerabilities

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