CVE-2026-25500

Rack's Stored XSS in Rack::Directory via javascript: filenames rendered into anchor href

MEDIUM
5.4
CVSS Score
Published: February 18, 2026 at 06:59 PM UTC
Updated: June 17, 2026 at 10:24 AM UTC
1 product affected across 1 vendorRack

Using rack by rack?

Get instant alerts when new vulnerabilities affect rack - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.4
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Rack· Rackrubygems
95%
v < 2.2.22v < 3.1.20v < 3.2.53.0.0 ≤ v < 3.1.203.2.0 ≤ v < 3.2.5
Affected range stops below 2.2.22, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.20, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.2.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/rack/rack/security/advisories/GHSA-whrj-4476-wvmp

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.4MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-79

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card