GHSA-fm8c-6m29-rp6j
MEDIUMrepostat: Reflected Cross-Site Scripting (XSS) via repo prop in RepoCard
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
repostatnpmDescription
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
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | repostat | all versions | 1.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for repostat. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update repostat to 1.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fm8c-6m29-rp6j is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-fm8c-6m29-rp6j is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-fm8c-6m29-rp6j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-fm8c-6m29-rp6j in your dependencies?
O3 detects GHSA-fm8c-6m29-rp6j across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.