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Fencer Vulns
medium 5.3

CVE-2026-56139 json

Apache Camel Undertow: The muteException consumer option defaulted to false, so a processing error returned the full Java stack trace in the HTTP response body, disclosing sensitive internal information to unauthenticated clients

published 2026-07-06 4 mo ago modified 2026-08-28 2 mo ago also EUVD-2026-41851 , GHSA-hjg2-f45w-c566

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 47%
public exploits
0
none known

Summary

Generation of Error Message Containing Sensitive Information vulnerability in Apache Camel Undertow Component.

The camel-undertow HTTP server consumer exposes a muteException option that controls what is returned to the client when a route processing error occurs. This option defaulted to false, whereas the other Camel HTTP server components (camel-http / camel-jetty / camel-servlet and camel-platform-http) default it to true. With muteException=false, when a request triggers an exception during route processing the consumer writes the full Throwable stack trace into the HTTP response body as text/plain instead of returning an empty body. Any unauthenticated client that can reach the endpoint and cause a processing error - for example by sending a malformed request body, an invalid parameter, or otherwise triggering a route-internal failure - therefore receives a complete Java stack trace. Such a stack trace can disclose sensitive internal information, including credentials embedded in exception messages, internal host names and IP addresses, filesystem paths, dependency and version details, database and class names, and the application's internal structure, which an attacker can use to plan further attacks. In addition, for Rest DSL consumers the muteException option was not honoured at all: the RestUndertowHttpBinding was created with a hard-coded false, so the stack trace was returned even when muteException=true had been configured. This issue affects Apache Camel: from 4.0.0 before 4.14.8, from 4.15.0 before 4.18.3, from 4.19.0 before 4.21.0.

Users are recommended to upgrade to version 4.21.0, which fixes the issue. If users are on the 4.14.x LTS releases stream, then they are suggested to upgrade to 4.14.8. If users are on the 4.18.x releases stream, then they are suggested to upgrade to 4.18.3. For deployments that cannot upgrade immediately, set muteException=true explicitly on the camel-undertow consumer (for example undertow: http://0.0.0.0:8080/api?muteException=true , or globally via the camel.component.undertow.mute-exception=true property), so that processing errors no longer return the stack trace to the client; note that on affected releases this workaround does not cover Rest DSL consumers, whose binding ignores the option until the fix is applied.

Patch / fix

  • maven org.apache.camel:camel-undertow 4.14.8, 4.18.3, 4.21.0
  • Apache Software Foundation Apache Camel Undertow 4.14.8, 4.18.3, 4.21.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-56139 updated cvss 5.3

org.apache.camel/camel-undertow: Apache Camel Undertow: Information disclosure via error messages containing sensitive data

  • Red Hat build of Apache Camel for Spring Boot 4 camel-undertow 4.18.1.redhat-00019 Red Hat Single Sign-On 7 camel-undertow 4.18.1.redhat-00019
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
GitHub 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem package affected fixed in
maven org.apache.camel:camel-undertow
>=4.0.0, <4.14.8
>=4.15.0, <4.18.3
>=4.19.0, <4.21.0
4.14.8
4.18.3
4.21.0

Affected products

  • Apache Software Foundation Apache Camel Undertow

Classification

Weakness
  • CWE-209 Generation of Error Message Containing Sensitive Information

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.