Th3 SpaceIOBlog
Practical posts from the community: Linux commands, security tools, how attacks work and how to start a career.
ls -lah: see everything in a folder, including what's hidden
Most people use ls and miss half of what it can tell them.
ls -lahSPACEIO // LINUXgrep -rni: find one line in a thousand files
Finding one line in a thousand files should take seconds, not hours.
grep -rni "password" .SPACEIO // LINUXfind: stop guessing where a file is
Where is that file? Stop guessing.
find / -name "*.conf" 2>/dev/nullSPACEIO // LINUXchmod 600: decide who can read your files
Who can read your files? On Linux, that's a setting.
chmod 600 fileSPACEIO // LINUXss -tulpn: what is your computer listening on right now?
What is your computer listening on right now?
ss -tulpnSPACEIO // LINUXtail -f: watch your system talk, live
Watch your system talk, live.
tail -f /var/log/syslogSPACEIO // LINUXhistory | grep: find the command you ran last week
You ran that command last week. What was it?
history | grep sshSPACEIO // LINUXcurl -I: what a website tells you before you open it
What is a website telling you before you even open it?
curl -I https://example.comSPACEIO // LINUXps aux: is that service running, or are you guessing?
Is that service running, or are you guessing?
ps aux | grep nginxSPACEIO // LINUXsort | uniq -c: let the terminal count for you
Which line shows up most? Let the terminal count.
sort file.txt | uniq -c | sort -nrSPACEIO // LINUXping: check the network before you blame the app
Before you blame the app, check the network.
ping -c 4 google.comSPACEIO // LINUXsha256sum: prove the file you downloaded is the real one
How do you know the file you downloaded is the real one?
sha256sum fileSPACEIO // CYBERSECURITYNmap: see what a network is showing the world
You can't secure what you can't see.
nmap -sV scanme.nmap.orgSPACEIO // CYBERSECURITYWireshark: read what's really on the network
Every app you use is talking. Wireshark lets you listen.
SPACEIO // CYBERSECURITYBurp Suite: see and change what your browser sends
A website only shows you what it wants you to see. The request tells the real story.
SPACEIO // CYBERSECURITYNetcat: the simplest way to talk to a port
Sometimes you just need to know if a port answers.
nc -zv host 80SPACEIO // CYBERSECURITYSQL injection: when a form talks to your database for the attacker
One text box, one apostrophe, and a login page can fall apart.
SPACEIO // CYBERSECURITYXSS: when a website runs the attacker's code in your browser
You trusted the site. The site trusted the input. That's the problem.
SPACEIO // CYBERSECURITYPhishing in four steps
Most breaches don't start with clever code. They start with a click.
SPACEIO // CYBERSECURITYRansomware in five steps
Nobody notices the first step. Everyone notices the last.
SPACEIO // NETWORKINGDNS: the phone book of the internet
You type a name. Your computer needs a number. DNS connects them.
dig example.comSPACEIO // CAREERFour ways into cybersecurity, none of them need a degree first
There is no single door into cybersecurity.
SPACEIO // ACADEMYEvery path starts with Linux and networking
Want to get into cybersecurity? Don't start with tools.