CVE-2020-11077.yml

---
gem: puma
cve: 2020-11077
ghsa: w64w-qqph-5gxm
url: https://github.com/puma/puma/security/advisories/GHSA-w64w-qqph-5gxm
date: 2020-05-22
title: HTTP Smuggling via Transfer-Encoding Header in Puma
description: |
  ### Impact

  This is a similar but different vulnerability to the one patched in 3.12.5 and 4.3.4.

  A client could smuggle a request through a proxy, causing the proxy to send a response
  back to another unknown client.

  If the proxy uses persistent connections and the client adds another request in via HTTP
  pipelining, the proxy may mistake it as the first request's body. Puma, however,
  would see it as two requests, and when processing the second request, send back
  a response that the proxy does not expect. If the proxy has reused the persistent
  connection to Puma to send another request for a different client, the second response
  from the first client will be sent to the second client.

  ### Patches

  The problem has been fixed in Puma 3.12.6 and Puma 4.3.5.
cvss_v3: 6.8
patched_versions:
  - "~> 3.12.6"
  - ">= 4.3.5"