CVE-2026-78437

What it is

Incomplete cleanup vulnerability in Apache Tomcat allows a malformed request to potentially (depends on timing) cause one request from another user to fail. This issue affects Apache Tomcat: from 11.0.19 through 11.0.25, from 10.1.53 through 10.1.59, from 9.0.116 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

At a glance

Exploitability

Can be exploited over the network without logging in. Limited direct impact.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-23 12:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-23 19:19 UTC Last updatedMost recent change to the record

Details

Published

2026-09-23 12:17 UTC

Last modified

2026-09-23 19:19 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-459

Record status

Awaiting Analysis

Attack profile CVSS 3.1 · 7.3

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

Low