repostat: Reflected Cross-Site Scripting (XSS) via repo prop in RepoCard
Date: 2026-02
Affected: npm/repostat
Attack vector: xss
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-27612
CWE: CWE-79
CVSS: 6.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

### Impact The `RepoCard` component is vulnerable to Reflected Cross-Site Scripting (XSS). The vulnerability occurs because the component uses React's `dangerouslySetInnerHTML` to render the repository name (`repo` prop) during the loading state without any sanitization. If a developer using this package passes unvalidated user input directly into the `repo` prop (for example, reading it from a URL query parameter), an attacker can execute arbitrary JavaScript in the context of the user's browser. ### Proof of Concept ```jsx import { RepoCard } from 'repostat'; function App() { const params = new URLSearchParams(window.location.search); const maliciousRepo = params.get('repo') || 'facebook/react'; return <RepoCard repo={maliciousRepo} token="YOUR_TOKEN" />; } ``` ### Remediation Update to version 1.0.1. The use of dangerouslySetInnerHTML has been removed, and the repo prop is now safely rendered using standard React JSX data binding, which automatically escapes HTML entities.


Mitigations:

Architectural layers (MAESTRO):