Bug: Unauthenticated /challenges/problems/seed endpoint allows arbitrary data insertion

[Siddh2024]

Bug

In src/main/java/.../SecurityConfig.java:74, the endpoint POST /challenges/problems/seed is publicly accessible with .permitAll(). Any unauthenticated user can insert arbitrary problems into the database.

Impact

Unauthenticated data injection - anyone can pollute the problems database.

Fix

Require authentication (ROLE_USER or ADMIN) for the seed endpoint.

@ashish-066 Please assign me this issue under GSSOC 2026.