Apache Tomcat up to 9.0.106/10.1.42/11.0.8 HTTP/2 Client resource consumption

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Apache Tomcat up to 9.0.106/10.1.42/11.0.8. The impacted element is an unknown function of the component HTTP2 Client Handler. The manipulation leads to resource consumption. This vulnerability is uniquely identified as CVE-2025-53506. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Apache Tomcat up to 9.0.106/10.1.42/11.0.8. This issue affects an unknown functionality of the component HTTP2 Client Handler. The manipulation with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. Impacted is availability. The summary by CVE is:

Uncontrolled Resource Consumption vulnerability in Apache Tomcat if an HTTP/2 client did not acknowledge the initial settings frame that reduces the maximum permitted concurrent streams. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.8, from 10.1.0-M1 through 10.1.42, 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 EOL versions may also be affected. Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.

The weakness was disclosed by Kanatoko. The advisory is shared at lists.apache.org. The identification of this vulnerability is CVE-2025-53506 since 07/01/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 241706 (Apache Tomcat 11.0.0.M1 < 11.0.9 multiple vulnerabilities), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.0.107, 10.1.43 or 11.0.9 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (241706), EUVD (EUVD-2025-21032) and CERT Bund (WID-SEC-2025-1468). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• IBM Power Hardware Management Console
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Apache Tomcat
• Red Hat JBoss Web Server
• Open Source Camunda
• IBM Integration Bus
• Atlassian Bamboo
• Atlassian Bitbucket
• Atlassian Jira
• Absolute Secure Access
• SAS Institute Base SAS
• Dell Secure Connect Gateway
• Dell NetWorker

Productinfo

Type

• Application Server Software

Vendor

• Apache

Name

• Tomcat

Version

• 9.0.106
• 10.1.0
• 10.1.1
• 10.1.2
• 10.1.3
• 10.1.4
• 10.1.5
• 10.1.6
• 10.1.7
• 10.1.8
• 10.1.9
• 10.1.10
• 10.1.11
• 10.1.12
• 10.1.13
• 10.1.14
• 10.1.15
• 10.1.16
• 10.1.17
• 10.1.18
• 10.1.19
• 10.1.20
• 10.1.21
• 10.1.22
• 10.1.23
• 10.1.24
• 10.1.25
• 10.1.26
• 10.1.27
• 10.1.28
• 10.1.29
• 10.1.30
• 10.1.31
• 10.1.32
• 10.1.33
• 10.1.34
• 10.1.35
• 10.1.36
• 10.1.37
• 10.1.38
• 10.1.39
• 10.1.40
• 10.1.41
• 10.1.42
• 11.0.0
• 11.0.1
• 11.0.2
• 11.0.3
• 11.0.4
• 11.0.5
• 11.0.6
• 11.0.7
• 11.0.8

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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