Networking

DNS, caching and network basics for websites and servers.

Security

CVE-2026-98432: Critical Linux Kernel TCP Vulnerability Scores 9.8

CVE-2026-98432 is a race-condition use-after-free in Linux kernel IPv4 TCP handling (tcp_v4_syn_recv_sock). The kernel CVE authority scores it 9.8, Red Hat 5.9; install your vendor's patched kernel and reboot.

Flushing the DNS cache on a computer and in a web browser

Networking

How to Clear the DNS Cache on Windows, Mac, Linux and Browsers

Run ipconfig /flushdns on Windows, sudo killall -HUP mDNSResponder on macOS, and the flush command for your Linux resolver, then clear the browser's own cache at chrome://net-internals/#dns or about:networking#dns.