puma on RubyGems
Puma is a simple, fast, threaded, and highly parallel HTTP 1.1 server for Ruby/Rack applications. Puma is intended for use in both development and production environments. It's great for highly parallel Ruby implementations such as Rubinius and JRuby as well as as providing process worker support to support CRuby well.
CVE History
| CVE | Published | CVSS v2 | CVSS v3 |
|---|---|---|---|
| CVE-2021-29509 | 7.5 HIGH | 5 MEDIUM | |
| Puma is a concurrent HTTP 1.1 server for Ruby/Rack applications. The fix for CVE-2019-16770 was incomplete. The original fix only protected existing connections that had already been accepted from having their requests starved by greedy persistent-connections saturating all threads in the same process. However, new connections may still be starved by greedy persistent-connections saturating all threads in all processes in the cluster. A `puma` server which received more concurrent `keep-alive` connections than the server had threads in its threadpool would service only a subset of connections, denying service to the unserved connections. This problem has been fixed in `puma` 4.3.8 and 5.3.1. Setting `queue_requests false` also fixes the issue. This is not advised when using `puma` without a reverse proxy, such as `nginx` or `apache`, because you will open yourself to slow client attacks (e.g. slowloris). The fix is very small and a git patch is available for those using unsupported versions of Puma. | |||