Essential linux commands for CTF, ethical hacking

campelo

Flavio Campelo

Posted on February 16, 2022

Essential linux commands for CTF, ethical hacking
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binwalk

The fastest way to check for embedded files and executable code

binwalk file.txt
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objdump in kali tools

objdump

Can display some important information from a file like its assembler mnemonics for the machine instructions

objdump -D file.bin
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man objdump

strings

It prints a sequence of printable caracteres from a file

strings -a file.txt
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man strings

exiftool

Read and write meta information in files

exiftool file.txt
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man exiftool

vim

A powerful text editor.

vim file.txt
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You can use vim to combine commands to edit a file.

For example, you can format a SQL query using sqlformat...

vim sqlFile.txt
:%! sqlformat --reindent --keywords upper --identifiers lower
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...or edit the hexcode of a file using xxd

vim file.txt
:%! xxd
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vim range tips

xxd

Used to see or modify the hex dump from a file.

xxd file.txt
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man xxd

stat

It displays information about the file

stat file.txt
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man stat

file

Determine the file type

stat file.txt
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man file

unzip

Commonly used to extract files from a zip file.

unzip file.zip
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man unzip

curl

You can use it to transfer data from or to a server.

curl http://mysite.com -H "Authorization: Bearer token"
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curl -X POST http://mysite.com -H "Authorization: Bearer token" -d "{ 'data': 'something' }"
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curl -I HEAD http://mysite.com
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man curl

wget

Download files from internet.

wget http://mysite.com/file
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man wget

Typos or suggestions?

If you've found a typo, a sentence that could be improved or anything else that should be updated on this blog post, you can access it through a git repository and make a pull request. If you feel comfortable with github, instead of posting a comment, please go directly to https://github.com/campelo/documentation and open a new pull request with your changes.

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campelo
Flavio Campelo

Posted on February 16, 2022

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