Images
binwalk
binwalk <file-name>
binwalk -e <file-name>
exiv2
exiv2 <file-name>
exiftool
exiftool <file-name>
steghide
steghide --extract -sf <file-name>
zbarimg for QR codes
zbarimg QR-code.png
stegsolve
wget http://www.caesum.com/handbook/Stegsolve.jar -O stegsolve.jar
chmod +x stegsolve.jar
java -jar stegsolve.jar
hexedit
hexedit <file-name>