CVE-2026-47737

Summary

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 Software

VendorProductVersion RangeStatus
pumapuma>= 5.5.0, < 7.2.1affected
pumapuma>= 8.0.0, < 8.0.2affected

Weaknesses

  • CWE-290: CWE-290: Authentication Bypass by Spoofing
  • CWE-345: CWE-345: Insufficient Verification of Data Authenticity

References