Vulnerability in Rack
CVE-2025-27111
Rack is a modular Ruby web server interface. The Rack::Sendfile middleware logs unsanitised header values from the X-Sendfile-Type header. An attacker can exploit this by injecting escape sequences (such as newline characters) into the header, resulting in log injection. This vulnerability is fixed in 2.2.12, 3.0.13, and 3.1.11.
Vulnerability class: CRLF Injection
EPSS: 0.007 (49.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Rack — versions < 2.2.12, >= 3.0, < 3.0.13, >= 3.1, < 3.1.11
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-27111?
- CVE-2025-27111 is a high-severity vulnerability in Rack, classified under CRLF Injection. CVSS score: 7.5/10. Published 2025-03-04.
- How severe is CVE-2025-27111?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-27111 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.