CVE-2025-27111: rack — Fix

Description

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.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-93 CWE-93

CWE-117 CWE-117

Affected Products

Vendor	Product	Versions
rack	rack	< 2.2.12
rack	rack	3.0.0 — 3.0.13
rack	rack	3.1.0 — 3.1.11

References

Advisories & Patches

https://github.com/rack/rack/commit/803aa221e8302719715e224f4476e438f2531a53 https://github.com/rack/rack/commit/aeac570bb8080ca7b53b7f2e2f67498be7ebd30b https://github.com/rack/rack/commit/b13bc6bfc7506aca3478dc5ac1c2ec6fc53f82a3 https://github.com/rack/rack/security/advisories/GHSA-8cgq-6mh2-7j6v

Other References

https://lists.debian.org/debian-lts-announce/2025/03/msg00016.html

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2025-27111? +

CVE-2025-27111 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-27111? +

CVE-2025-27111 affects products from rack, specifically: rack. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-27111? +

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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