high7.5
CVE-2025-53506
Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams
Impact
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. Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | org.apache.tomcat:tomcat-coyote | >= 11.0.0-M1, < 11.0.9 | 11.0.9 |
| maven | org.apache.tomcat.embed:tomcat-embed-core | >= 8.5.0, <= 8.5.100 | none recorded |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Apache | Tomcat | from 9.0.0 through 9.0.106 from 10.1.0 through 10.1.42 from 11.0.0 through 11.0.8 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://lists.apache.org/thread/p09775q0rd185m6zz98krg0fp45j8kr0
- http://www.openwall.com/lists/oss-security/2025/07/10/13
- https://lists.debian.org/debian-lts-announce/2025/07/msg00009.html
- https://github.com/advisories/GHSA-25xr-qj8w-c4vf
- https://nvd.nist.gov/vuln/detail/CVE-2025-53506
- https://github.com/apache/tomcat/commit/2aa6261276ebe50b99276953591e3a2be7898bdb
- https://github.com/apache/tomcat/commit/434772930f362145516dd60681134e7f0cf8115b
- https://github.com/apache/tomcat/commit/be8f330f83ceddaf3baeed57522e571572b6b99b