VulnerabilityModified

CVE-2025-25184

The supplied proof-of-concept demonstrates injecting malicious content into logs.

MEDIUM 5.7EPSS 1.19%

Does this matter?

Lower severity and a low EPSS score (1.19%). Track it; it rarely justifies an emergency change on its own.

Description

Rack provides an interface for developing web applications in Ruby. Prior to versions 2.2.11, 3.0.12, and 3.1.10, Rack::CommonLogger can be exploited by crafting input that includes newline characters to manipulate log entries. The supplied proof-of-concept demonstrates injecting malicious content into logs. When a user provides the authorization credentials via Rack::Auth::Basic, if success, the username will be put in env['REMOTE_USER'] and later be used by Rack::CommonLogger for logging purposes. The issue occurs when a server intentionally or unintentionally allows a user creation with the username contain CRLF and white space characters, or the server just want to log every login attempts. If an attacker enters a username with CRLF character, the logger will log the malicious username with CRLF characters into the logfile. Attackers can break log formats or insert fraudulent entries, potentially obscuring real activity or injecting malicious data into log files. Versions 2.2.11, 3.0.12, and 3.1.10 contain a fix.

CVSS 4.0: 5.7 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 1.19% probability · 66th percentile
CISA KEV: Not listed
Weakness: CWE-93, CWE-117
Affected: rack/rack
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.