CVE-2026-56677: 9Router: Authenticated Server-Side Request Forgery (SSRF) via OIDC Provider Test Endpoint

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-17 · updated 2026-10-23
Weakness: CWE-306

Description

9Router is an AI router & token saver. In 0.5.4 and earlier, the POST /api/auth/oidc/test endpoint in src/app/api/auth/oidc/test/route.js passes the user-controlled issuerUrl parameter to fetchOidcDiscovery() in src/lib/auth/oidc.js without restricting private or loopback destinations, allowing unauthenticated attackers when dashboard login is disabled to scan internal services and reflect OIDC discovery fields including token_endpoint and jwks_uri.

Affected products

decolua 9router: through 0.5.4

References

https://github.com/decolua/9router/security/advisories/GHSA-8g4w-4ffg-8vgx
https://github.com/decolua/9router/security/advisories/GHSA-8g4w-4ffg-8vgx

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