CVE-2026-25500
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account, but needs a user to act. Limited direct impact.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 5.4 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-79 · Cross-site scripting
- Record status
- Analyzed
Affected
- Rack < 2.2.22
- Rack < 3.1.20
- Rack < 3.2.5
Attack profile CVSS 3.1 · 5.4
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-25500.md and follow it. Check whether this project is affected by CVE-2026-25500. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/rack/rack/commit/f2f225f297b99fbee3d9f51255d41f601fc40aff
- https://github.com/rack/rack/security/advisories/GHSA-whrj-4476-wvmp