---
id: CVE-2023-42794
title: >-
  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 poten…
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 poten…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-459
vendor: apache
product: tomcat
affected:
  - 'tomcat >= 8.5.85, < 8.5.94'
  - 'tomcat >= 9.0.70, < 9.0.81'
patched:
  - tomcat 9.0.81
published: '2023-10-10'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T22:17:25.113'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-42794'
references:
  - url: 'https://lists.apache.org/thread/vvbr2ms7lockj1hlhz5q3wmxb2mwcw82'
    label: security@apache.org
  - url: 'http://www.openwall.com/lists/oss-security/2023/10/10/8'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.apache.org/thread/vvbr2ms7lockj1hlhz5q3wmxb2mwcw82'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.01854
epssPercentile: 0.7852
ingestedAt: '2026-10-08T23:16:47.352Z'
---

## Overview

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.

## Affected

- `tomcat >= 8.5.85, < 8.5.94`
- `tomcat >= 9.0.70, < 9.0.81`

## Remediation

Upgrade past the affected range:

- `tomcat 9.0.81`