CVE-2026-47737
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.
- Affected products
- Puma
- Fix
- Available
- CVSS 3.1
- 7.5 HIGH
- EPSS
- 0.2% (7th percentile)
- Weakness
- CWE-345, CWE-290
- NVD status
- Deferred
- Published
- 2026-07-14
CVE-2026-47737 at NVD
No indexed exploits for CVE-2026-47737 yet
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No exploit for CVE-2026-47737 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.