vulnerability
Apache Tomcat: Important: HTTP/2 DoS (CVE-2020-11996)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:L/Au:N/C:N/I:N/A:P) | Jun 26, 2020 | Jun 26, 2020 | Mar 27, 2026 |
Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
Jun 26, 2020
Added
Jun 26, 2020
Modified
Mar 27, 2026
Description
A specially crafted sequence of HTTP/2 requests sent to Apache Tomcat 10.0.0-M1 to 10.0.0-M5, 9.0.0.M1 to 9.0.35 and 8.5.0 to 8.5.55 could trigger high CPU usage for several seconds. If a sufficient number of such requests were made on concurrent HTTP/2 connections, the server could become unresponsive.
Solutions
apache-tomcat-upgrade-8_5_56apache-tomcat-upgrade-9_0_36
Rapid7 Labs
2026 Global Threat Landscape Report
The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.