High 7.5Published Jul 14, 2026

CVE-2026-47737Puma PROXY Protocol v1 Accepts Repeated Protocol Headers on Persistent Connections

Updated under an hour ago (Oct 26, 2026, 3:30 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for puma

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness (CWE): CWE-290, CWE-345
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Jul 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

puma puma puma:puma (from the name)	from 5.5.0, < 7.2.1; from 8.0.0, < 8.0.2	CNA record

References

https://github.com/puma/puma/security/advisories/GHSA-2vqw-3mp8-cgmxx-refsource-confirm
https://github.com/puma/puma/pull/3944x-refsource-misc
https://github.com/puma/puma/pull/3947x-refsource-misc
https://github.com/puma/puma/commit/439c6136d9c2275721b7864db3ee78af7c80889fx-refsource-misc
https://github.com/puma/puma/commit/ebe9db3929ab8299d19c8f5b41e8ef4f4b22fa58x-refsource-misc
https://github.com/puma/puma/releases/tag/v7.2.1x-refsource-misc
https://github.com/puma/puma/releases/tag/v8.0.2x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.