CVE-2026-25500

Publication date 18 February 2026

Last updated 27 February 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Rack is a modular Ruby web server interface. Prior to versions 2.2.22, 3.1.20, and 3.2.5, `Rack::Directory` generates an HTML directory index where each file entry is rendered as a clickable link. If a file exists on disk whose basename starts with the `javascript:` scheme (e.g. `javascript:alert(1)`), the generated index contains an anchor whose `href` is exactly `javascript:alert(1)`. Clicking the entry executes JavaScript in the browser (demonstrated with `alert(1)`). Versions 2.2.22, 3.1.20, and 3.2.5 fix the issue.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ruby-rack	25.10 questing	Fixed 3.1.16-0.1ubuntu0.2
	24.04 LTS noble	Fixed 2.2.7-1ubuntu0.6
	22.04 LTS jammy	Fixed 2.1.4-5ubuntu1.2+esm2
	20.04 LTS focal	Fixed 2.0.7-2ubuntu0.1+esm9
	18.04 LTS bionic	Ignored changes too intrusive
	16.04 LTS xenial	Ignored changes too intrusive
	14.04 LTS trusty	Ignored changes too intrusive

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
ruby-rack	Upstream: f2f225f Upstream: 93a68f5 Upstream: ed0f455 Upstream: 175e7d2

Severity score breakdown

Parameter	Value
Base score	5.4 · Medium
Attack vector	Network
Attack complexity	Low
Privileges required	Low
User interaction	Required
Scope	Changed
Confidentiality	Low
Integrity impact	Low
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

Related Ubuntu Security Notices (USN)

USN-8066-1
Rack vulnerabilities
26 February 2026