Puma is a Ruby/Rack web server built for parallelism. Prior to versions 6.3.1 and 5.6.7, puma exhibited incorrect behavior when parsing chunked transfer encoding bodies and zero-length Content-Length headers in a way that allowed HTTP request smuggling. Severity of this issue is highly dependent on the nature of the web site using puma is. This could be caused by either incorrect parsing of trailing fields in chunked transfer encoding bodies or by parsing of blank/zero-length Content-Length headers. Both issues have been addressed and this vulnerability has been fixed in versions 6.3.1 and 5.6.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.
CVSS Details
- CVSS 3.1 Base Score: 7.3
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | debian-upgrade-puma | Mar 17, 2025 | Aug 18, 2023 | |
| Suse | — | suse-upgrade-ruby2-5-rubygem-pumasuse-upgrade-ruby2-5-rubygem-puma-doc | Oct 5, 2023 | Aug 18, 2023 |
| Ubuntu | ubuntu-pro-upgrade-pumaubuntu-upgrade-puma | Sep 28, 2023 | Aug 18, 2023 |
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