DEBIAN-CVE-2026-125110: Medium severity debian/ruby-rack vulnerability

Q: Which deployments are affected in practice?

Only applications using Rack::Static with path-specific header_rules are affected. Applications that do not configure path-specific header_rules are not affected.

Q: What does an attacker need to exploit this issue?

An attacker does not need authentication or user interaction. They need to request a known static file using raw or percent-encoded dot segments so that the served path differs from the path evaluated by the header rules.

Q: What is the impact of a successful request?

The attacker can receive a known file without path-specific security headers, including headers such as Content-Disposition or Content-Security-Policy. The supplied severity vector indicates integrity impact but no confidentiality or availability impact.

Q: Which Rack versions contain the fixes?

The issue is fixed in Rack versions 2.2.25, 3.1.23, and 3.2.8. Versions prior to those releases in their respective release lines are affected when the vulnerable Rack::Static header_rules configuration is in use.

Published Nov 9, 2026

Updated

Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Static serves a path after Utils.cleanpathinfo normalization but evaluates headerrules against a path that is only URL-decoded. An unauthenticated attacker can request a known file through raw or percent-encoded dot segments and receive it without path-specific security headers such as Content-Disposition or Content-Security-Policy. Applications that do not use path-specific headerrules are not affected. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8.

Affected Software

3 affected componentsFixes available

debian/ruby-rack*

debian/ruby-rack<3.2.8-1

3.2.8-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/ruby-rack to a version that resolves this vulnerability.
Fixed in 3.2.8-1
Upgrade
Upgrade Rack::Static to a version that resolves this vulnerability.
Fixed in 2.2.25
Upgrade
Upgrade Rack::Static to a version that resolves this vulnerability.
Fixed in 3.1.23
Upgrade
Upgrade Rack::Static to a version that resolves this vulnerability.
Fixed in 3.2.8

Event History

Nov 9, 2026

CVE Published

via OSV·10:18 PM

Data Sourced

via OSV·10:18 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which deployments are affected in practice?

Only applications using Rack::Static with path-specific header_rules are affected. Applications that do not configure path-specific header_rules are not affected.

What does an attacker need to exploit this issue?

An attacker does not need authentication or user interaction. They need to request a known static file using raw or percent-encoded dot segments so that the served path differs from the path evaluated by the header rules.

What is the impact of a successful request?

The attacker can receive a known file without path-specific security headers, including headers such as Content-Disposition or Content-Security-Policy. The supplied severity vector indicates integrity impact but no confidentiality or availability impact.

Which Rack versions contain the fixes?

The issue is fixed in Rack versions 2.2.25, 3.1.23, and 3.2.8. Versions prior to those releases in their respective release lines are affected when the vulnerable Rack::Static header_rules configuration is in use.

DEBIAN-CVE-2026-125110: Medium severity debian/ruby-rack vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Which deployments are affected in practice?

What does an attacker need to exploit this issue?

What is the impact of a successful request?

Which Rack versions contain the fixes?

Company

Resources

Contact

Frequently Asked Questions

Which deployments are affected in practice?

What does an attacker need to exploit this issue?

What is the impact of a successful request?

Which Rack versions contain the fixes?