# CVE-2025-53506: Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams

Source: https://junglewise.ai/threats/cve-2025-53506-apache-tomcat-coyote-vulnerable-to-denial-of-service-via  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-07-10  
License: CC BY 4.0 with a link back

CVE-2025-53506 · Severity: low · CVSS 3.1 · Published 2025-07-10

Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams

Technologies: [org.apache.tomcat:tomcat-coyote (Maven)](https://junglewise.ai/threats/technologies/org-apache-tomcat-tomcat-coyote), [org.apache.tomcat.embed:tomcat-embed-core (Maven)](https://junglewise.ai/threats/technologies/org-apache-tomcat-embed-tomcat-embed-core). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2025-53506 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-53506 being exploited in the wild.

**How severe is CVE-2025-53506?** Low severity, with a CVSS score of 3.1, published 10 July 2025.

**Which products and versions are affected?** org.apache.tomcat:tomcat-coyote (Maven) ECOSYSTEM:introduced=11.0.0-M1,fixed=11.0.9; org.apache.tomcat.embed:tomcat-embed-core (Maven) ECOSYSTEM:introduced=8.5.0,last_affected=8.5.100.

**Is there a fix for CVE-2025-53506?** Yes. org.apache.tomcat:tomcat-coyote (Maven): upgrade to 11.0.9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-53506?** Check whether you run org.apache.tomcat:tomcat-coyote (Maven) or org.apache.tomcat.embed:tomcat-embed-core (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- org.apache.tomcat:tomcat-coyote (Maven): upgrade to 11.0.9 or later

  ```sh
  # set org.apache.tomcat:tomcat-coyote to 11.0.9 in your pom.xml or build.gradle
  ```


## Affected products

- org.apache.tomcat:tomcat-coyote (Maven) ECOSYSTEM:introduced=11.0.0-M1,fixed=11.0.9
- org.apache.tomcat.embed:tomcat-embed-core (Maven) ECOSYSTEM:introduced=8.5.0,last_affected=8.5.100

## Identifiers

- CVE-2025-53506
- GHSA-25xr-qj8w-c4vf

## Related threats

- [Apache Tomcat FORM authentication authorization bypass](https://junglewise.ai/threats/cve-2026-68525-apache-tomcat-form-authentication-authorization-bypass)
- [Apache Tomcat DIGEST authenticator authentication bypass](https://junglewise.ai/threats/cve-2026-65905-apache-tomcat-digest-authenticator-authentication-bypass)
- [Apache Tomcat improper input validation in incomplete fix](https://junglewise.ai/threats/cve-2026-65637-apache-tomcat-improper-input-validation-in-incomplete-fix)
- [Apache Tomcat security constraint bypass](https://junglewise.ai/threats/cve-2026-65182-apache-tomcat-security-constraint-bypass)
- [Apache Tomcat authentication bypass in JNDIRealm](https://junglewise.ai/threats/cve-2026-55957-apache-tomcat-authentication-bypass-in-jndirealm)