Puma is a web server for Ruby/Rack applications built for parallelism. Prior to version 6.4.2, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies in a way that allowed HTTP request smuggling. Fixed versions limits the size of chunk extensions. Without this limit, an attacker could cause unbounded resource (CPU, network bandwidth) consumption. This vulnerability has been fixed in versions 6.4.2 and 5.6.8.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade puma | Nov 11, 2024 | Jan 8, 2024 |
| Suse | — | Upgrade ruby2.5-rubygem-pumaUpgrade ruby2.5-rubygem-puma-doc | Dec 5, 2025 | Oct 16, 2024 |
| Ubuntu | — | Upgrade pumaUpgrade puma (Ubuntu Pro) | Jan 26, 2024 | Jan 8, 2024 |
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