GHSA-36rg-gfq2-3h56
Fix: better-auth/better-auth@9801d1bGHSA-36rg-gfq2-3h56 is a Open Redirect vulnerability in better-auth. O3 Security confirms whether GHSA-36rg-gfq2-3h56 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Better Auth Open Redirect Vulnerability in originCheck Middleware Affects Multiple Routes
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
better-authnpmDescription
Summary
An open redirect has been found in the originCheck middleware function, which affects the following routes: /verify-email, /reset-password/:token, /delete-user/callback, /magic-link/verify, /oauth-proxy-callback.
Details
In the matchesPattern function, url.startsWith( can be deceived with a url that starts with one of the trustedOrigins.
const matchesPattern = (url: string, pattern: string): boolean => {
if (url.startsWith("/")) {
return false;
}
if (pattern.includes("*")) {
return wildcardMatch(pattern)(getHost(url));
}
return url.startsWith(pattern);
};
Open Redirect PoCs
export const auth = betterAuth({
baseURL: 'http://localhost:3000',
trustedOrigins: [
"http://trusted.com"
],
emailAndPassword: {
...
},
})
/reset-password/:token
<img width="481" alt="image" src="https://github.com/user-attachments/assets/46e7871a-1dad-4375-af94-0446e29aaab6" />
<br/>
<img width="518" alt="image 1" src="https://github.com/user-attachments/assets/83abfb53-6fc9-4d1f-918d-9b4ce093c808" />
/verify-email
<img width="549" alt="image" src="https://github.com/user-attachments/assets/7dd424b7-42a4-4616-aa73-fcc2e3eeb309" />
<br/>
<img width="436" alt="image" src="https://github.com/user-attachments/assets/54f11636-0a3e-4e83-9a09-57c5e8ba98cd" />
/delete-user/callback
<img width="545" alt="image" src="https://github.com/user-attachments/assets/2ff1b217-d069-48fb-81c1-f8c8792d34a4" />
<br/>
<img width="492" alt="image" src="https://github.com/user-attachments/assets/71df11db-9d38-4f34-abe1-add9d60b3486" />
/magic-link/verify
<img width="379" alt="image" src="https://github.com/user-attachments/assets/6b6b6a8a-59b6-4a65-9df3-57d5b2f6eb0f" />
<br/>
<img width="413" alt="image" src="https://github.com/user-attachments/assets/82a5c9c6-2ea0-44eb-af48-40732657b59e" />
/oauth-proxy-callback
<img width="548" alt="image" src="https://github.com/user-attachments/assets/d8d2ee51-e9fd-4337-bec3-a70afd1ceacb" />
<br/>
<img width="544" alt="image" src="https://github.com/user-attachments/assets/f097d406-b965-4f85-b124-9b0ef1cc2689" />
Impact
Untrusted open redirects in various routes.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | better-auth | all versions | 1.2.10 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for better-auth. 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 better-auth to 1.2.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-36rg-gfq2-3h56 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-36rg-gfq2-3h56 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-36rg-gfq2-3h56. 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-36rg-gfq2-3h56 in your dependencies?
O3 detects GHSA-36rg-gfq2-3h56 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.