Apache Tomcat Incomplete Cleanup vulnerability

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2023-42795: 2.51% estimated exploitation activity in the next 30 days; percentile 84.83 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Incomplete Cleanup vulnerability in Apache Tomcat. When recycling various internal objects in Apache Tomcat from 11.0.0-M1 through 11.0.0-M11, from 10.1.0-M1 through 10.1.13, from 9.0.0-M1 through 9.0.80 and from 8.5.0 through 8.5.93, an error could cause Tomcat to skip some parts of the recycling process leading to information leaking from the current request/response to the next. Older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M12 onwards, 10.1.14 onwards, 9.0.81 onwards or 8.5.94 onwards, which fixes the issue.

Published by the source

10 Oct 2023, 18:31 UTC

Last modified by the source

12 Jun 2026, 19:50 UTC

Source last checked

26 Oct 2026, 16:53 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-g8pj-r55q-5c2v

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# Patch Next advisory brief: CVE-2023-42795

Advisory: Apache Tomcat Incomplete Cleanup vulnerability
IDs: CVE-2023-42795, GHSA-g8pj-r55q-5c2v
Record: https://patchnext.com/advisories/cve-2023-42795 (revision 1, source checked 26 Oct 2026, 16:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.apache.tomcat:tomcat-catalina 11.0.0-M12, 10.1.14, 9.0.81, 8.5.94; org.apache.tomcat:tomcat-util 11.0.0-M12, 10.1.14, 9.0.81, 8.5.94; org.apache.tomcat.embed:tomcat-embed-core 11.0.0-M12, 10.1.14, 9.0.81, 8.5.94; org.apache.tomcat:tomcat 11.0.0-M12, 10.1.14, 9.0.81, 8.5.94. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.apache.tomcat:tomcat-catalina: affected >= 11.0.0-M1, < 11.0.0-M12; >= 10.1.0-M1, < 10.1.14; >= 9.0.0-M1, < 9.0.81; >= 8.5.0, < 8.5.94; fixed in 10.1.14, 9.0.81, 11.0.0-M12, 8.5.94
- Maven org.apache.tomcat:tomcat-util: affected >= 11.0.0-M1, < 11.0.0-M12; >= 10.1.0-M1, < 10.1.14; >= 9.0.0-M1, < 9.0.81; >= 8.5.0, < 8.5.94; fixed in 10.1.14, 9.0.81, 11.0.0-M12, 8.5.94
- Maven org.apache.tomcat.embed:tomcat-embed-core: affected >= 11.0.0-M1, < 11.0.0-M12; >= 10.1.0-M1, < 10.1.14; >= 9.0.0-M1, < 9.0.81; >= 8.5.0, < 8.5.94; fixed in 10.1.14, 9.0.81, 11.0.0-M12, 8.5.94
- Maven org.apache.tomcat:tomcat: affected >= 9.0.0-M1, < 9.0.81; >= 8.5.0, < 8.5.94; >= 11.0.0-M1, < 11.0.0-M12; >= 10.1.0-M1, < 10.1.14; fixed in 10.1.14, 9.0.81, 11.0.0-M12, 8.5.94

## Suggested inspection (read-only)
- Maven org.apache.tomcat:tomcat-catalina: check the installed version with your package manager.
- Maven org.apache.tomcat:tomcat-util: check the installed version with your package manager.
- Maven org.apache.tomcat.embed:tomcat-embed-core: check the installed version with your package manager.
- Maven org.apache.tomcat:tomcat: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.apache.tomcat:tomcat-catalina, org.apache.tomcat:tomcat-util, org.apache.tomcat.embed:tomcat-embed-core, org.apache.tomcat:tomcat.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-g8pj-r55q-5c2v (GitHub-reviewed advisory GHSA-g8pj-r55q-5c2v lists affected ranges: Maven org.apache.tomcat:tomcat >=9.0.0-M1 =8.5.0 =11.0.0-M1 =10.1.0-M1 =11.0.0-M1 =10.1.0-M1 =9.0.0-M1 =8.5.0 =11.0.0-M1 =10.1.0-M1 =9.0.0-M1 =8.5.0 =11.0.0-M1…)

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