CVE-2024-45614

Header normalization allows for client to clobber proxy set headers in Puma

Severity Score

5.4

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

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.

USN-7031-1 fixedCVE-2024-45614 in Puma for Ubuntu 24.04 LTS. This update fixes theCVE for Ubuntu 22.04 LTS and Ubuntu 20.04 LTS. It was discovered that Puma incorrectly handled parsing certain headers. A remote attacker could possibly use this issue to overwrite header values set by intermediate proxies by providing duplicate headers containing underscore characters.

*Credits: N/A

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

High

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-09-02 CVE Reserved
2024-09-19 CVE Published
2024-09-20 CVE Updated
2024-09-29 First Exploit
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-639: Authorization Bypass Through User-Controlled Key

CAPEC

References (3)

URL	Tag	Source
https://github.com/puma/puma/security/advisories/GHSA-9hf4-67fc-4vf4	X_refsource_confirm
https://nginx.org/en/docs/http/ngx_http_core_module.html#underscores_in_headers	X_refsource_misc

URL	Date	SRC
https://github.com/ooooooo-q/puma_header_normalization-CVE-2024-45614	2024-09-29

URL	Date	SRC

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Puma Search vendor "Puma"		Puma Search vendor "Puma" for product "Puma"				>= 6.0.0 < 6.4.3 Search vendor "Puma" for product "Puma" and version " >= 6.0.0 < 6.4.3"		en		Affected
Puma Search vendor "Puma"		Puma Search vendor "Puma" for product "Puma"				< 5.6.9 Search vendor "Puma" for product "Puma" and version " < 5.6.9"		en		Affected