---
title: "CVE-2026-65637\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-65637?format=md
keywords: index, follow
---

# CVE-2026-65637

Publication date 25 August 2026

Last updated 2 September 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2026-65637?format=md#impact-score)

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## Description

Improper Input Validation vulnerability in Apache Tomcat due to incomplete
fix for CVE-2026-32990.
This issue affects Apache Tomcat: from 11.0.20 through 11.0.24, from
10.1.53 through 10.1.57, from 9.0.115 through 9.0.120.
Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121,
which fix the issue.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2026-65637?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| tomcat6 | 26.04 LTS resolute | Not in release |
| 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Needs evaluation |
| tomcat7 | 26.04 LTS resolute | Not in release |
| 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release |
| 18.04 LTS bionic | Not affected |
| 16.04 LTS xenial | Needs evaluation |
| 14.04 LTS trusty | Needs evaluation |
| tomcat8 | 26.04 LTS resolute | Not in release |
| 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release |
| 18.04 LTS bionic | Needs evaluation |
| 16.04 LTS xenial | Needs evaluation |
| tomcat9 | 26.04 LTS resolute | Needs evaluation |
| 24.04 LTS noble | Needs evaluation |
| 22.04 LTS jammy | Needs evaluation |
| 20.04 LTS focal | Needs evaluation |
| 18.04 LTS bionic | Needs evaluation |
| tomcat10 | 26.04 LTS resolute | Needs evaluation |
| 24.04 LTS noble | Needs evaluation |
| 22.04 LTS jammy | Not in release |
| tomcat11 | 26.04 LTS resolute | Needs evaluation |
| 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Notes

---

### [ebarretto](https://launchpad.net/~ebarretto)

xenial tomcat6 only builds libservlet2.5-java, not the Tomcat
server binaries
bionic tomcat7 only builds libservlet3.0-java, not the Tomcat
server binaries
xenial tomcat6 only builds libservlet2.5-java, not the Tomcat
server binaries
bionic tomcat7 only builds libservlet3.0-java, not the Tomcat
server binaries
xenial tomcat6 only builds libservlet2.5-java, not the Tomcat
server binaries
bionic tomcat7 only builds libservlet3.0-java, not the Tomcat
server binaries

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

9.8 · Critical

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 9.8 · Critical |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-65637)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-65637)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-65637)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-65637)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-65637>
* <https://github.com/apache/tomcat/commit/8639b20f045c88f356b887204f52e897399f0de7 (11.0.25)>
* <https://github.com/apache/tomcat/commit/40012414df828a56126f76a7339669c7c919aae7 (10.1.58)>
* <https://github.com/apache/tomcat/commit/b823e88da077f5fa973e34d72359bded9f621e3c (9.0.121)>
