CVE-2024-45614: puma Request Smuggling — Fix

Description

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.

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CVSS v3.1 Score

5.4

MEDIUM

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

Weakness Type (CWE)

CWE-639 CWE-639

CWE-444 CWE-444

Affected Products

Vendor	Product	Versions
puma	puma	< 5.6.9
puma	puma	6.0.0 — 6.4.3

References

Advisories & Patches

https://github.com/puma/puma/security/advisories/GHSA-9hf4-67fc-4vf4

Other References

https://nginx.org/en/docs/http/ngx_http_core_module.html#underscores_in_headers https://lists.debian.org/debian-lts-announce/2024/11/msg00004.html

Frequently Asked Questions

What is CVE-2024-45614? +

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. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2024-45614? +

CVE-2024-45614 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-45614? +

CVE-2024-45614 affects products from puma, specifically: puma. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-45614? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2024-45614