CVE-2026-49352
CRITICAL9Router: Hardcoded Default fallback JWT Secret Allows Authentication Bypass
Blast Radius
9routerReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
9Router is an AI router & token saver. From 0.2.21 until 0.4.44, 9Router used the hardcoded fallback JWT secret 9router-default-secret-change-me in src/app/api/auth/login/route.js, src/middleware.js, and later src/lib/auth/dashboardSession.js, allowing attackers to forge an auth_token cookie when JWT_SECRET was unset. This issue is fixed in version 0.4.44
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | 9router | ≥ 0.2.21&&< 0.4.45 | 0.4.45 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for 9router. 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 9router to 0.4.45 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-49352 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 CVE-2026-49352 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 CVE-2026-49352. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-49352 in your dependencies?
O3 detects CVE-2026-49352 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.