Race Condition in Vote/Review System
By @gorkaMarketplace donde el sistema de votos y reviews tiene race conditions que permiten votar multiples veces y dejar multiples reviews para destruir la reputacion de un producto.
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Despliegue
# Opcion 1: autodeploy
./autodeploy.sh
# Opcion 2: manual
docker compose up --build
# Acceder
https://localhost:1000
Compatible con macOS, Linux y Windows (Docker Desktop / WSL).
Para parar:
./autodeploy.sh destroy
# o: docker compose down -v
Contenido del Lab
La aplicacion
TrustMart es un marketplace con sistema de votos (like/dislike) y reviews con estrellas.
La vulnerabilidad
Los endpoints de votar (POST /api/products/:id/vote) y review (POST /api/reviews/product/:id) verifican si el usuario ya voto/reviewo con delay antes de registrar la accion. Peticiones concurrentes bypasean el check de unicidad.
Cadena de ataque
1. Votar normalmente → 1 voto registrado
2. Intentar votar de nuevo → bloqueado
3. Enviar 50 votos dislike concurrentes → todos pasan
4. Enviar 15 reviews 1-estrella concurrentes
5. Reputacion del producto destruida
Solucion interactiva
Accede a /writeup dentro de la aplicacion para una guia paso a paso con botones interactivos.
Flag
(reputacion del producto destruida)
Remediacion
- UNIQUE constraint en la base de datos (user_id + product_id)
- Transacciones atomicas
- INSERT ... ON CONFLICT DO NOTHING
