Dangerous: iptables -P INPUT ACCEPT

Dangerous

iptables -P INPUT ACCEPT

linux · bash · Beginner

Sets the default policy for inbound traffic to ACCEPT. Any packet that does not match an explicit rule is now allowed, which quietly inverts a firewall built on the assumption that unmatched traffic is dropped.

Signals to notice

-P changes the default policy, which applies to everything unmatched
ACCEPT as a default turns a deny-by-default firewall into allow-by-default

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