#VU105794 CRLF injection in Rack - CVE-2025-25184

Vulnerability identifier: #VU105794

Vulnerability risk: Low

CVSSv4.0: 0.6 [CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-25184

CWE-ID: CWE-93

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Rack
Web applications / Modules and components for CMS

Vendor: Rack

Description

The vulnerability allows a remote user to manipulate data log entries.

The vulnerability exists due to insufficient validation of attacker-supplied data in Rack::CommonLogger. A remote user can pass specially crafted authorization credentials containing CR-LF characters to the Rack::Auth::Basic method, which stores this info into the to the env['REMOTE_USER'] variable. If the application accepts CR-LF characters in user name, a remote user can manipulate data log entries.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Rack: 2.2.0 - 2.2.10, 3.0.0 - 3.0.10, 3.1.0 - 3.1.10

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External links
https://github.com/rack/rack/commit/074ae244430cda05c27ca91cda699709cfb3ad8e
https://github.com/rack/rack/security/advisories/GHSA-7g2v-jj9q-g3rg

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.