CVE-2026-33929: Apache PDFBox Examples: Path Traversal in PDFBox ExtractEmbeddedFiles Example Code

[Tilman Hausherr <tilman () apache org>]

Severity: low 

Affected versions:

- Apache PDFBox Examples (org.apache.pdfbox:pdfbox-examples) 2.0.24 through 2.0.36
- Apache PDFBox Examples (org.apache.pdfbox:pdfbox-examples) 3.0.0 through 3.0.7

Description:

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Apache PDFBox Examples.

This issue affects the 
ExtractEmbeddedFiles example in Apache PDFBox: from 2.0.24 through 2.0.36, from 3.0.0 through 3.0.7.


Users are recommended to update to version 2.0.37 or 3.0.8 once 
available. Until then, they should apply the fix provided in GitHub PR 
427.

The ExtractEmbeddedFiles example contained a path traversal vulnerability (CWE-22) mentioned in CVE-2026-23907. However 
the change in the releases 2.0.36 and 3.0.7 is flawed because it doesn't consider the file path separator. Because of 
that, a user having writing rights on /home/ABC could be victim to a malicious PDF resulting in a write attempt to any 
path starting with /home/ABC, e.g. "/home/ABCDEF".

Users who have copied this example into their production code should apply the mentioned change. The example 
has been changed accordingly and is available in the project repository.

This issue is being tracked as PDFBOX-6180 

Credit:

Kaixuan Li (finder)

References:

https://github.com/apache/pdfbox/pull/427/changes
https://lists.apache.org/thread/op3lyx1ngzy4qycn06l6hljyf28ff0zs
https://pdfbox.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-33929
https://issues.apache.org/jira/browse/PDFBOX-6180