ICMP timestamp请求响应漏洞CVE-1999-0524解决方法
1、添加进和出的规则
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT 0 -p ICMP --icmp-type timestamp-request -m comment --comment "deny ICMP timestamp" -j DROP
firewall-cmd --permanent --direct --add-rule ipv4 filter OUTPUT 0 -p ICMP --icmp-type timestamp-request -m comment --comment "deny ICMP timestamp" -j DROP
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT 0 -p ICMP --icmp-type timestamp-reply -m comment --comment "deny ICMP timestamp" -j DROP
firewall-cmd --permanent --direct --add-rule ipv4 filter OUTPUT 0 -p ICMP --icmp-type timestamp-reply -m comment --comment "deny ICMP timestamp" -j DROP
以上包括了进和出的规则
只是封进的规则可以只填两条
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT 0 -p ICMP --icmp-type timestamp-request -m comment --comment "deny ICMP timestamp" -j DROP
firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT 0 -p ICMP --icmp-type timestamp-reply -m comment --comment "deny ICMP timestamp" -j DROP
防火墙重启载入规则
firewall-cmd --reload
查看添加规则
firewall-cmd --direct --get-all-rules
如果看不到规则，则重启防火墙systemctl restart firewalld
