Apache POI OOXML Vulnerable to Improper Input Validation in OOXML File Parsing
Published Apr 9, 2025 · Updated Nov 3, 2026
Original summary
Normalized public record · Updated Nov 3, 2026
Apache POI OOXML Vulnerable to Improper Input Validation in OOXML File Parsing
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
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.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Apr 9, 2025 · Last refreshed Nov 3, 2026