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Auto-Blacklisting: Let AI Block Repeat Offenders

Manual blacklist management doesn't scale. Every minute you spend adding malicious IPs to a blacklist is a minute attackers are using to probe your defenses. You need automation.

SecZim's auto-blacklist feature identifies malicious behavior and blocks offenders automatically—no human intervention required.

How Auto-Blacklisting Works

1

Behavior Detection

SecZim monitors every connection for signs of malicious activity

2

Threshold Tracking

Counts violations per IP: SPF failures, rate limit hits, policy rejections

3

Automatic Blocking

When threshold exceeded, IP is automatically added to blacklist

4

Alert Notification

Admin receives instant notification of new block

Configurable Triggers

Define exactly what behavior triggers automatic blocking. Every organization has different needs—SecZim adapts to yours.

SPF Failures

Block IPs that repeatedly fail SPF verification

Rate Limit Violations

Auto-block aggressive senders who hit rate limits

Policy Rejections

Block IPs triggering your security policies

Invalid Recipients

Block IPs sending to non-existent addresses

Threshold Customization

Not all violations are equal. Configure different thresholds for different violation types:

  • 5 SPF failures in 1 hour → Block for 24 hours
  • 10 rate limit hits in 30 minutes → Block for 1 week
  • 50 invalid recipient attempts → Permanent block
  • Any violation from blocked country → Permanent block

Self-Defending Infrastructure

Auto-blacklisting creates a self-defending email system. The more attackers probe, the stronger your defenses become. Every attack attempt trains your system to recognize and block similar threats.

IP Reputation Tracking

SecZim maintains a reputation score for every IP that connects to your server. Good behavior improves scores; bad behavior decreases them. Low-reputation IPs face stricter scrutiny and faster blacklisting.

Reputation Factors

  • Historical violation count
  • Time since last violation
  • Geographic risk level
  • Volume of legitimate email sent
  • SPF/DKIM pass rates

Temporary vs. Permanent Blocks

Not every violation deserves a permanent ban. SecZim supports graduated responses:

  • First offense: 1-hour temporary block
  • Second offense: 24-hour block
  • Third offense: 1-week block
  • Fourth offense: Permanent blacklist

This graduated approach catches legitimate senders who make occasional mistakes while permanently blocking persistent attackers.

Whitelist Protection

Worried about blocking legitimate senders? Whitelisted IPs, domains, and email addresses are never auto-blacklisted. Your trusted partners are always protected.

Complete Visibility

See exactly what's being auto-blocked and why:

  • Real-time alerts when IPs are blacklisted
  • Complete history of violations per IP
  • One-click unblock for false positives
  • Export blacklist for analysis

Set It and Forget It Security

Stop manually managing blacklists. Let SecZim's auto-blacklist feature block bad actors automatically.

Start Free Trial

The Power of Automation

Auto-blacklisting transforms your email security from reactive to proactive. Instead of responding to attacks after the damage is done, you're blocking attackers before they succeed.

Your email server learns. It adapts. It defends itself.