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Advanced Auth & Tenant Security
Abuse Protection
Defend login and signup flows with rate limits, lockouts, CAPTCHA checks, and anomaly signals.
7 min readBuilding Backend ApplicationsBuild
Abuse Vectors
Login and signup endpoints are the most attacked surfaces. Credential stuffing, brute force, account enumeration, and spam signups are constant threats. Each requires a different defense strategy.
Rate Limiting
Goper-endpoint-rate-limiting.go
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Rate limit login attempts per IP (5 per 15 minutes) and signup attempts per IP (3 per hour). These are stricter than general API rate limits.
Account Lockouts
Goprogressive-lockout.go
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Progressive lockout: 5 failures in 15 minutes triggers a 1-hour lockout. Successful login clears the counter. This prevents brute force while allowing legitimate typos.
CAPTCHA Integration
Gocaptcha-verification.go
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Only require CAPTCHA after repeated attempts. This keeps the signup experience smooth for legitimate users while blocking bots.
Anomaly Detection
Gologin-anomaly-signals.go
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Track login locations, devices, and attempt counts. When anomalies are detected, send an alert email or require additional verification. This catches compromised credentials.
IP Reputation
- Block known VPN and proxy IPs for signup.
- Flag IPs with high failed login rates.
- Use IP geolocation to detect impossible travel.
- Integrate with threat intelligence feeds.
- Consider Cloudflare or similar for advanced protection.
Do not block legitimate users
Rate limiting and lockouts must be carefully tuned. If you block legitimate users, they will not come back. Use progressive challenges (CAPTCHA) before hard blocks.
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