CVE-2024-45614 Header normalization allows for client to clobber proxy set headers in Puma

2024-09-1922:42:33

CWE-639

GitHub_M

www.cve.org

cve-2024-45614

puma

header normalization

proxy clobbering

ruby web server

security update

nginx mitigation

CVSS3

5.4

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

EPSS

0.001

Percentile

17.7%

JSON

Puma is a Ruby/Rack web server built for parallelism. In affected versions clients could clobber values set by intermediate proxies (such as X-Forwarded-For) by providing a underscore version of the same header (X-Forwarded_For). Any users relying on proxy set variables is affected. v6.4.3/v5.6.9 now discards any headers using underscores if the non-underscore version also exists. Effectively, allowing the proxy defined headers to always win. Users are advised to upgrade. Nginx has a underscores_in_headers configuration variable to discard these headers at the proxy level as a mitigation. Any users that are implicitly trusting the proxy defined headers for security should immediately cease doing so until upgraded to the fixed versions.

CNA Affected

[
  {
    "vendor": "puma",
    "product": "puma",
    "versions": [
      {
        "version": ">= 6.0.0, < 6.4.3",
        "status": "affected"
      },
      {
        "version": "< 5.6.9",
        "status": "affected"
      }
    ]
  }
]