CVE-2026-47737
Puma PROXY Protocol v1 Accepts Repeated Protocol Headers on Persistent Connections
- State
- Published
- Severity
- 7.5 High
- Published
- Jul 14, 2026
- Updated
- Jul 15, 2026
- Reserved
- May 19, 2026
Description
Puma is a Ruby/Rack web server built for parallelism. From 5.5.0 until 7.2.1 and 8.0.2, Puma is vulnerable to source IP spoofing when set_remote_address proxy_protocol: :v1 is enabled and persistent connections are used because Puma incorrectly re-parses PROXY protocol headers after each keep-alive request on the same connection, allowing an attacker to inject a second PROXY header and overwrite REMOTE_ADDR. This issue is fixed in versions 7.2.1 and 8.0.2.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N | GitHub_M |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
pumapuma |
|
References
- https://github.com/puma/puma/security/advisories/GHSA-2vqw-3mp8-cgmx
- https://github.com/puma/puma/pull/3944
- https://github.com/puma/puma/pull/3947
- https://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889f
- https://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58
- https://github.com/puma/puma/releases/tag/v7.2.1
- https://github.com/puma/puma/releases/tag/v8.0.2
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