Advisory [CVE-2023-42794] Apache Tomcat: FileUpload: DoS due to accumulation of temporary files on Windows
This Apache Software Foundation security advisory covers CVE-2023-42794 affecting Apache Tomcat.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published
Summary
Incomplete Cleanup vulnerability in Apache Tomcat.
The internal fork of Commons FileUpload packaged with Apache Tomcat 9.0.70 through 9.0.80 and 8.5.85 through 8.5.93 included an unreleased, in progress refactoring that exposed a potential denial of service on
Windows if a web application opened a stream for an uploaded file but failed to close the stream.
The file would never be deleted from disk creating the possibility of an eventual denial of service due to the
disk being full.
Other, EOL versions may also be affected.
Users are recommended to upgrade to version 9.0.81 onwards or 8.5.94 onwards, which fixes the issue.
Is CVE-2023-42794 exploited?
No exploitation is reported in the sources VulniPulse tracks: CVE-2023-42794 is not in the CISA KEV catalog (checked ) and this advisory does not report exploitation. That is not proof the vulnerability cannot be exploited.
How do I fix CVE-2023-42794?
Upgrade to a fixed release named by Apache:
- 9.0.81
- 8.5.94
Confirm against the vendor advisory before you patch.
- Apache Tomcat 9.0.70 through 9.0.80
- Apache Tomcat 8.5.85 through 8.5.93
Official advisory · medium-confidence parse· fetched 1 month ago·verify at source
- 9.0.81
- 8.5.94
Official advisory · medium-confidence parse· fetched 1 month ago·verify at source
Mitigation checklist
- Users are recommended to upgrade to version 9.0.81 onwards or 8.5.94 onwards, which fixes the issue.
Official advisory · medium-confidence parse· fetched 1 month ago·verify at source
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