---
id: "CVE-2026-80353"
kind: "vulnerability"
aliases: ["CVE-2026-80353"]
title: "Apache Tomcat: APR/Native connector socket race lets local users access socket"
severity: "low"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["java", "linux", "runtime", "self-hosted", "tomcat"]
not_affected_if: ["multi-user-host-absent", "nio-connector-only", "no-apr-native", "tomcat-10-or-11"]
published_at: "2026-10-20T14:17:03+00:00"
first_seen_at: "2026-10-23T21:57:20+00:00"
updated_at: "2026-10-25T05:04:47+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80353", "first_seen_at": "2026-10-23T21:57:20+00:00"}]
---

# Apache Tomcat: APR/Native connector socket race lets local users access socket

When Tomcat creates a Unix domain socket for the APR/Native connector, a race condition between the check and the creation step lets a local user access that socket. The fix for CVE-2026-65183 covered only the NIO connector, so the APR/Native connector remains exposed.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `catalina.sh version` or check the Tomcat version in the server banner; affected range is `9.0.47` through `9.0.122`
- Check whether the APR/Native connector is in use: look for `Connector` elements with `protocol="org.apache.coyote.http11.Http11AprProtocol"` or the APR library loaded in `conf/server.xml`

## Fix

- Upgrade Apache Tomcat 9 to `9.0.123`

## Timeline

- 2026-10-23T21:57:20+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-80353

## From the sources

Time-of-check time-of-use (TOCTOU) race condition vulnerability in Apache Tomcat when creating unix domain sockets for the APR/Native connector allows an unauthorised local user to access the unix domain socket. The fix for CVE-2026-65183 only addressed the NIO connector. It did not address the same issue in the APR/Native connector.



This issue affects Apache Tomcat: from 9.0.47 through 9.0.122.



Users are recommended to upgrade to version 9.0.123, which fixes the issue.

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