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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using cat from sorted by
Terminal - Commands using cat - 444 results
rm index.html | wget www.google.com;cat index.html | sed 's/<script>/\n\n\<script>\n\n/g' | sed 's/<\/script>/>\n\n/g'
2013-04-10 04:05:30
User: lbhack
Functions: cat rm sed wget

remove old index.html if you download it again and organiaz the java script tag on the file index.html

cat /sys/block/md1/holders/dm*/dm/name | awk -F- '{print $1}' | sort -u
cat /sys/block/{*,*/*}/holders/dm*/dm/name | awk -F- '{print $1}' | sort -u
for a in $(seq 5 8); do cat twit.txt | cut -d " " -f$a | grep "^@" | sort -u; done > followlst.txt
2013-03-29 21:07:09
User: xmuda
Functions: cat cut grep seq sort

Go to "https://twitter.com/search/realtime?q=%23TeamFollowBack&src=hash" and then copy al the text on the page. If you scroll down the page will be bigger. Then put al the text in a text file called twit.txt

If you follow the user there is a high probability the users give you follow back.

To follow all the users you can use an iMacros script.

cat -s
while read line; do export $line; done < <(cat input)
2013-03-15 08:14:04
User: dario
Functions: cat export read

This exports all lines of input file as environment variables, assuming each line is like these:



cat /var/lib/dpkg/info/*.md5sums|grep usr/sbin/sshd|sed 's,usr,/usr,'|md5sum -c
2013-03-12 11:20:48
User: Ztyx
Functions: cat grep md5sum sed

Replace "user/sbin/sshd" with the file you would like to check. If you are doing this due to intrusion, you obviously would want to check size, last modification date and md5 of the md5sum application itself. Also, note that "/var/lib/dpkg/info/*.md5sums" files might have been tampered with themselves. Neither to say, this is a useful command.

echo "ls" > script.bash; gpg -c script.bash; cat script.bash.gpg | gpg -d --no-mdc-warning | bash
2013-03-10 09:34:12
User: betsubetsu
Functions: cat echo gpg

echo "ls" > script.bash;

This is my script, a simple 'ls'.

gpg -c script.bash;

Here I encrypt and passord-protect my script. This creates file script.bash.gpg.

cat script.bash.gpg | gpg -d --no-mdc-warning | bash

Here I open file script.bash.gpg, decrypt it and execute it.

read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
2013-03-10 08:59:45
User: rodolfoap
Functions: cat chmod echo gpg read sed wc

(Please see sample output for usage)

Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.:

myscript --> myscript.crypt

You can execute myscript.crypt only if you know the password. If you die, your script dies with you.

If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string).

Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner.

Sorry for the chmod on parentheses, I dont like "-" at the end.

Thanks flatcap for the subshell abbreviation to /dev/null

cat item_list | xargs -n1 -P<n> process_item
cat /proc/cpuinfo | grep " lm " > /dev/null && echo 64 bits || echo 32 bits
2013-02-11 22:54:26
User: agd
Functions: cat echo grep

CPU flags:

rm --> 16-bit processor (real mode)

tm --> 32-bit processor (? mode)

lm --> 64-bit processor (long mode)

if [[ lm = $(cat /proc/cpuinfo | grep " lm ") ]] ; then echo "64 bits" ; else echo "32 bits" ; fi
2013-02-11 22:40:46
User: agd
Functions: cat echo grep

CPU flags:

rm --> 16-bit processor (real mode)

tm --> 32-bit processor (? mode)

lm --> 64-bit processor (long mode)

find . -type f -name "*.txt" | while read; do (($(cat $THISFILE | wc -l) < 10)) && rm -vf "$THISFILE"; done
dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
2013-01-31 01:38:30
User: rodolfoap

This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it.


The file is composed of three parts:

a) The legible script (about 242 bytes)

b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242)

c) The actual filesystem

Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option.

PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :)

It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file.

The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables.

for i in {a..z}; do echo $(cat ~/.bash_history | grep ^$i.* | wc -l) $i; done | sort -n -r
2013-01-23 18:59:13
User: yaMatt
Functions: cat echo grep sort wc

Kind of fun if you're that was inclined. I figured most of my commands start with s. sudo, screen, ssh etc. This script tells me what else they start with.

cat somefile | tee >(openssl md5 > sum.md5) | bzip2 > somefile.bz2
cat *mscache* | awk -F '"' '{print $4":"$2}'
2013-01-06 06:54:57
User: mubix
Functions: awk cat

Convert Metasploit?s MSCACHE output to Hashcat version (performed in ~/.msf4/loot/):

cat list.txt | pax -wd > archive.tar
cat /dev/zero | pv -L 3m -Ss 100m > /dev/null
2012-12-15 10:17:52
User: bugmenot
Functions: cat

This example will close the pipe after transferring 100MB at a speed of 3MB per second.

cat ~/.ssh/id_rsa.pub | ssh [email protected] 'cat >> ~/.ssh/authorized_keys'
cat myfile | tee dest1 dest2 > /dev/null 2>&1
while sleep 1; do clear; cat /tmp/whatever.cue; done
cd ~/.msf4/loot && cat *mscache* | cut -d '"' -f 2,4 | sed s/\"/\:/g | tr -cd '\11\12\40-\176' | grep -v Username | cut -d : -f 1,2 | awk -F':' '{print $2,$1}' | sed 's/ /:/g' > final.dcc.hash
cat dump.sql | sed -n -e '/Table structure for table .table1./,/Table structure for table .table2./p'
2012-11-22 23:54:04
User: infojunkie
Functions: cat sed
Tags: mysql sed

Given a dump.sql file, extract table1 creation and data commands. table2 is the one following table1 in the dump file. You can also use the same idea to extract several consecutive tables.