CVE-2025-31672: Apache POI: parsing OOXML based files (xlsx, docx, etc.), poi-ooxml could read unexpected data if underlying zip has duplicate zip entry names

[PJ Fanning <fanningpj () apache org>]

Severity: moderate

Affected versions:

- Apache POI before 5.4.0

Description:

Improper Input Validation vulnerability in Apache POI. The issue affects the parsing of OOXML format files like xlsx, 
docx and pptx. These file formats are basically zip files and it is possible for malicious users to add zip entries 
with duplicate names (including the path) in the zip. In this case, products reading the affected file could read 
different data because 1 of the zip entries with the duplicate name is selected over another but different products may 
choose a different zip entry.
This issue affects Apache POI poi-ooxml before 5.4.0. poi-ooxml 5.4.0 has a check that throws an exception if zip 
entries with duplicate file names are found in the input file.
Users are recommended to upgrade to version poi-ooxml 5.4.0, which fixes the issue. Please read  
https://poi.apache.org/security.html  for recommendations about how to use the POI libraries securely.

This issue is being tracked as bug-69620 

References:

https://bz.apache.org/bugzilla/show_bug.cgi?id=69620
https://poi.apache.org/
https://www.cve.org/CVERecord?id=CVE-2025-31672
https://issues.apache.org/jira/browse/bug-69620