A misordered rule is a firewall or security policy entry placed in the wrong position in a rule chain. Many firewalls evaluate rules top to bottom, so an earlier match can stop later rules from ever being checked. Even a correct rule can fail to protect traffic if a broader allow, deny, or exception appears above it.
This matters because attackers often benefit from logic gaps, while defenders rely on precise ordering to block, allow, or inspect traffic as intended. A misordered rule can create an unintended bypass, hide a needed exception, or make a security control look effective when it is never reached. In practice, security teams look for misordered rules during audits, using hit counts, packet traces, and policy reviews to confirm that important rules are actually being evaluated. Good rule ordering is part of configuration hygiene and helps keep firewall behavior aligned with policy.