A couple of new CVEs were issued for Tomcat, including one with a severity
designation of 'important' (see below). Please be sure to keep your Tomcat
installations up-to-date with the most current version available.
CVE-2021-25122 h2c request mix-up
> Severity: Important
> Vendor: The Apache Software Foundation
> Versions Affected:
> Apache Tomcat 10.0.0-M1 to 10.0.0
> Apache Tomcat 9.0.0.M1 to 9.0.41
> Apache Tomcat 8.5.0 to 8.5.61
> When responding to new h2c connection requests, Apache Tomcat could
> duplicate request headers and a limited amount of request body from one
> request to another meaning user A and user B could both see the results
> of user A's request.
> Users of the affected versions should apply one of the following
> - Upgrade to Apache Tomcat 10.0.2 or later
> - Upgrade to Apache Tomcat 9.0.43 or later
> - Upgrade to Apache Tomcat 8.5.63 or later
> Note that issue was fixed in 10.0.1, 9.0.42 and 8.5.62 but the release
> votes for those versions did not pass.
> This issue was identified by the Apache Tomcat Security Team.
> 2021-03-01 Original advisory
>  https://tomcat.apache.org/security-10.html
>  https://tomcat.apache.org/security-9.html
>  https://tomcat.apache.org/security-8.html
>  https://tomcat.apache.org/security-7.html