diff --git a/.devcontainer/init-firewall.sh b/.devcontainer/init-firewall.sh
index aa01872..062fcfd 100644
--- a/.devcontainer/init-firewall.sh
+++ b/.devcontainer/init-firewall.sh
@@ -114,7 +114,7 @@ iptables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
 iptables -A OUTPUT -m set --match-set allowed-domains dst -j ACCEPT
 
 # Explicitly REJECT all other outbound traffic for immediate feedback
-iptables -A OUTPUT -j REJECT --reject-with icmp-port-unreachable
+iptables -A OUTPUT -j REJECT --reject-with icmp-admin-prohibited
 
 echo "Firewall configuration complete"
 echo "Verifying firewall rules..."