Linux
SSH ProxyJump: Reach a Server Through a Jump Host
A server that only accepts SSH from one static IP does not need your private key on that IP. Tested ProxyJump setups, the errors you will see and how to lock down the jump host.
Topic
security
Web
PHP2Shell: Check, Patch and Restart Your PHP Servers
Two critical PHP bugs fixed on 21 October 2026 can let one request run code on your server. How to find the PHP that serves your site, check the version, restart it and block the known paths.
Linux
Xtables-addons: GeoIP, TARPIT and the psd Module I Ported
Extra iptables matches and targets the kernel never shipped: country blocking with geoip, a TARPIT decoy port, port knocking, and the psd scan detector I ported.
Web
How nginx Chooses a location Block: Prefixes, Regexes and ^~
Not first match, not longest match, but a mix of both. A test config where every location names itself shows exactly how nginx picks one, and where it surprises.
Programming
Python subprocess.run() Instead of os.system()
Why I convert os.system() calls to subprocess.run(): no shell injection, real exit codes, captured output, timeouts and input, with notes for Python 3.6.
Web
nginx try_files Explained: Static Sites and PHP Front Controllers
try_files checks files in order and only the last argument redirects. Static clean URLs, a PHP front controller with php-fpm, and the upload exploit it prevents.
Linux
Docker Volumes vs Bind Mounts, and the File Ownership Trap
Why a volume shows the image's files and a bind mount hides them, and how a root container leaves files your own user cannot edit or delete. Four tested fixes.
Linux
Docker Multi-Stage Builds: Smaller Images, Same Result
The same 147 kB binary in a 257 MB image or an 8.44 MB one. Multi-stage builds, named stages, a --target debug image, and why build secrets still leak.