Severity:
CVSS 3.1: 5.4 (medium) CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Affected versions:
- Apache Camel (org.apache.camel:camel-docling) 4.15.0 before 4.18.5
- Apache Camel (org.apache.camel:camel-docling) 4.19.0 before 4.22.2
Description:
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
vulnerability in Apache Camel Docling component.
This issue affects Apache Camel: from 4.15.0 before 4.18.5, from 4.19.0 before
4.22.2.
DoclingProducer runs the external docling tool in CLI mode, the default, and
tells it where to write the converted document through the --output flag. When
the CamelDoclingOutputFilePath header was set, addOutputDirectoryArguments
handed its value to that flag verbatim: the value was not normalized, an
absolute path or a path containing .. segments was accepted as given, and no
endpoint option could confine it to a directory. The custom-argument validation
added by the fix for CVE-2026-40047 refuses the --output and -o flags in the
CamelDoclingCustomArguments header and tells callers to choose the output
directory with this header instead, so the one value that decides where docling
writes reached the command line without any of the checks applied to custom
arguments. Docling writes the conversion result, as Markdown, HTML, JSON or
text, into that directory, naming the file after the input file, and the
producer afterwards removes only its own temporary directory, so the file is
left in place. A party able to set the header could therefore have conversion
output created in any directory the Camel process can write to. The content of
such a file is the conversion of the document carried by the message, so it is
shaped by whoever supplies that document without being written byte for byte,
and when the document content arrives in the message body the producer stores
it under a random temporary name, which the output file then carries. The
header belongs to the Camel header namespace, which consumers applying Camel's
default header filtering, such as the JMS and Kafka consumers, remove from
incoming messages, so the issue is reached where a route forwards externally
influenced values into the header or where a consumer maps incoming headers
without that filtering. The docling-serve mode does not use the header.
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 fix adds an outputBaseDirectory endpoint option that is
unset by default, so after upgrading, set it on every docling endpoint whose
CamelDoclingOutputFilePath header can carry a value influenced from outside the
deployment; without it the header is normalized but can still name any
directory. 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 build the CamelDoclingOutputFilePath header
from values that originate outside the deployment, remove that header from
messages that arrive from outside before they reach a docling endpoint, and
make sure that consumers which map incoming message headers drop the Camel
header namespace, so that only the route itself chooses the output directory.
Solution:
Upgrade to Apache Camel 4.23.0, which fixes the issue. Users on the 4.22.x
stream should upgrade to 4.22.2 and users on the 4.18.x stream should upgrade
to 4.18.5. The CamelDoclingOutputFilePath header is now normalized before it
reaches docling, and a new outputBaseDirectory endpoint option confines it:
when the option is set, a value that resolves outside that directory, including
an absolute path, is rejected with an IOException before docling is started.
The option is unset by default, so it must be set after upgrading wherever the
header can carry a value influenced from outside the deployment; without it the
header is normalized but can still name any directory. 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.
Work Arounds:
Do not build the CamelDoclingOutputFilePath header from values that originate
outside the deployment, remove that header from messages that arrive from
outside before they reach a docling endpoint, and make sure that consumers
which map incoming message headers drop the Camel header namespace, so that
only the route itself chooses the output directory.
Credit:
Zhixi "Jace" Sun, independent security researcher (finder)
Andrea Cosentino (remediation developer)
References:
https://camel.apache.org/security/CVE-2026-95629.html
https://issues.apache.org/jira/browse/CAMEL-24894
https://github.com/apache/camel/pull/26737
https://github.com/apache/camel/pull/27365
https://github.com/apache/camel/pull/27362
https://camel.apache.org/security/CVE-2026-40047.html
https://camel.apache.org/security/CVE-2026-78163.html
https://camel.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-95629
