CVE-2025-27111 — Escape Sequence Injection vulnerability in rack —...

MEDIUM

Escape Sequence Injection vulnerability in Rack lead to Possible Log Injection

Published March 4, 2025Updated September 10, 2026Source: osv

Summary

## Summary `Rack::Sendfile` can be exploited by crafting input that includes newline characters to manipulate log entries. ## Details The `Rack::Sendfile` middleware logs unsanitized 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. ## Impact This vulnerability can distort log files, obscure attack traces, and complicate security auditing. ## Mitigation - Update to the latest version of Rack, or - Remove usage of `Rack::Sendfile`.

Advisory Timeline

First published March 4, 2025 (587 days ago).
Last revised September 10, 2026 — 555 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Bundler

Update rack to 3.0.13 or later

gem install rack -v 3.0.13

Bundler

Update rack to 2.2.12 or later

gem install rack -v 2.2.12

Bundler

Update rack to 3.1.11 or later

gem install rack -v 3.1.11

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (3)

Affects 1 ecosystem: rubygems (1).

Package	Ecosystem	Affected	Fixed In
rack	rubygems	3.0.0, 3.0.1, 3.0.10, 3.0.11 (+13 more)	3.0.13
rack	rubygems	0.1.0, 0.2.0, 0.3.0, 0.4.0 (+108 more)	2.2.12
rack	rubygems	3.1.0, 3.1.1, 3.1.10, 3.1.2 (+7 more)	3.1.11

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-117
View on MITRE
CWE-93
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 5.3 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Confidentiality

—

Integrity

—

Availability

—

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

References

Frequently Asked Questions

What is CVE-2025-27111?: Escape Sequence Injection vulnerability in Rack lead to Possible Log Injection This vulnerability has been assigned a severity rating of MEDIUM (CVSS score: 5.3/10).
How do I check if my project is affected by CVE-2025-27111?: CVE-2025-27111 affects rack. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2025-27111 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

5.3

Exploitation requires specific conditions or has limited impact. Remediate within weeks.

Also Known As

GHSA-8cgq-6mh2-7j6v

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