Packet filtering firewall is one of the most important mechanisms used by corporations to enforce their security policy. Recent years have seen a lot of research in the area of firewall management.

A group of hackers that security researchers call LightBasin has been compromising mobile telecommunication systems across the world for the past five years. Since 2019, the group hacked into more ...

The Dockerfile builds iptables into the image. The dist/iptables-wrapper-installer.sh script says it "installs a wrapper iptables script in a container that will figure out whether iptables-legacy or ...

When you log in to the computer, if you see a message box with an error message saying “Can not find script file” in Windows 11 and Windows 10, this post may help ...

# iptables -A INPUT -p tcp -m tcp -m multiport ! --dports 80,443 -j DROP # iptables -A INPUT -p tcp -m tcp -m multiport --dports 80,443 -j ACCEPT # iptables -A INPUT -m conntrack -j ACCEPT --ctstate ...

After securing systems by hiding them completely from the network/internet using Single Packet Authorization, I’ve recently been interested in doing more so-called ‘active’ defense, by implementing ...

Iptables, more properly referred to as “iptables/netfilter” because of the two modules that are involved — the userspace module “iptables” and the kernel ...

Dear readers, I appear to have set a Paranoid Penguin record—six months spent on one article series. (It has consisted of five installments, with a one-month break between the second and third pieces.

I've been writing a multipart series on building a transparent (bridging) firewall using Linux. Specifically, I'm using the distribution OpenWrt running on a Linksys WRT54GL broadband router, a ...