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--- PENTEST


check .bash_history
check tmp directory

=========================FILE IDENTIFICATION
file backup.bz2 
backup.bz2: bzip2 compressed data, block size = 400k
========================UNCOMPRESSION
tar -xf archive.tar.xz
tar -xjf test.tbz
tar -zxvf backup.tgz
gunzip -c backup.tgz | tar xvf -
bzip2 -d filename.bz2
bunzip2 backup.bz2
cpio -idv < ../new.cpio
cpio -idv --no-absolute-filename < backup
strings backup

wget -c ftp://ftp.vim.org/pub/vim/unix/vim-8.1.tar.bz2 -O - | sudo tar -xj
=========================ENCRYPT/DECRYPT
#To encrypt the contents of the current working directory 
tar -czf - * | openssl enc -e -aes256 -out secured.tar.gz

--
encrypt:
openssl enc -aes256 -k mypassword -in /tmp/backup.tar -out /tmp/backup.tar.enc
decrypt:
openssl enc -d -aes256 -k mypassword -in /tmp/backup.tar.enc -out /tmp/backup.tar

--
-----best way to do it with salt
HowTo: Encrypt a File #always use -salt option
$ openssl enc -aes-256-cbc -salt -in file.txt -out file.txt.enc

HowTo: Decrypt a File
$ openssl enc -aes-256-cbc -d -in file.txt.enc -out file.txt
---


=========================DIRECTORY
The directory /tmp does get cleanup after each reboot. 
The directory /var/tmp does not get cleanup after each reboot. 
/etc/cron.daily/ # cron jobs run daily listed

========================SEARCH

find /home -name .bash_history -exec grep -A 1 passwd {} \;
find . -name .bash_history -exec grep -A 1 '^passwd' {} \;

=====================USER
To see list of logged in user type who or w command:
saurus@proton:~$ who
results:
saurus   :0           2021-10-18 21:59 (:0)


To logout a user called elliot:
# pkill -KILL -u elliot
$sudo pkill -KILL -u elliot




=====================CHECK WEBSITE
#check site ssl certificate dates:

echo | openssl s_client -connect www.johlem.net:443 2>/dev/null |openssl x509 -dates -noout

#results:
notBefore=Sep 14 02:19:26 2021 GMT
notAfter=Dec 13 02:19:25 2021 GMT


=====================MAC ADRESS

#Generate a Random MAC address:

openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'

#generate password:
openssl rand -base64 25
#results:
JiJzuyFMRxW9a0uqzaBPAovVB20XRAnYkA==

============================DESTROY
Securely destroy data on given device hugely faster than /dev/urandom

This command generates a pseudo-random data stream using aes-256-ctr with a seed set by /dev/urandom. Redirect to a block device for secure data scrambling.

4
openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > randomfile.bin
s






























# to kill all process on the server and root too: //warning, don't do this!!!
pkill -KILL -u root

====================