CVE-2025-53506 — Apache Tomcat: DoS via excessive h2 streams at connection start

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
Apache Software Foundation / Apache Tomcat	affected 11.0.0-M1 through 11.0.8; affected 10.1.0-M1 through 10.1.42; affected 9.0.0.M1 through 9.0.106; affected 8.5.0 through 8.5.100; unknown 10.0.0-M1 through 10.0.27

CWE

CWE-400

References

https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

CVE

No English description supplied.