OverTheWire - Bandit - Level 15 to Level 16

Description:

Level Goal

The password for the next level can be retrieved by submitting the password of the current level to port 30001 on localhost using SSL encryption.

Helpful note: Getting "HEARTBEATING" and "Read R BLOCK"? Use -quiet and read the "CONNECTED COMMANDS" section in the manpage. Next to 'R' and 'Q', the 'B' command also works in this version of that command...

Commands you may need to solve this level

ssh, telnet, nc, openssl, s_client, nmap

Helpful Reading Material

Secure Socket Layer/Transport Layer Security on Wikipedia
Testing SSL with commandline tools

Solution:

1. [Comment] Using SSH to connect the server
2. sp@simple-plan:~|=> ssh bandit15@bandit.labs.overthewire.org
   ...
   bandit15@bandit.labs.overthewire.org's password: BfMYroe26WYalil77FoDi9qh59eK5xNr
3. [Comment] Using openssl with s_client option to establish the encrypted communication
4. bandit15@melinda:~$ echo BfMYroe26WYalil77FoDi9qh59eK5xNr | openssl s_client -quiet -connect localhost:30001
   depth=0 CN = localhost
   verify error:num=18:self signed certificate
   verify return:1
   depth=0 CN = localhost
   verify return:1
   Correct!
   cluFn7wTiGryunymYOu4RcffSxQluehd
   
   read:errno=0
5. [Comment] Using exit command to disconnect connection to server
6. bandit15@melinda:~$ exit
   logout
   Connection to bandit.labs.overthewire.org closed.
7. [Comment] It's done! Saving the password for next level.

Reference:

ssh	http://linuxcommand.org/man_pages/ssh1.html
ls	http://linuxcommand.org/man_pages/ls1.html
cat	http://linuxcommand.org/man_pages/cat1.html
exit	http://linuxcommand.org/man_pages/exit1.html
cd	http://linuxcommand.org/lc3_man_pages/cdh.html
find	http://linuxcommand.org/man_pages/find1.html
grep	http://linuxcommand.org/lc3_man_pages/grep1.html
sort	http://linuxcommand.org/lc3_man_pages/sort1.html
uniq	http://linuxcommand.org/man_pages/uniq1.html
strings	http://linuxcommand.org/man_pages/strings1.html
base64	http://linux.die.net/man/1/base64
tr	http://linuxcommand.org/man_pages/tr1.html
alias	http://linuxcommand.org/man_pages/alias1.html
mkdir	http://linuxcommand.org/man_pages/mkdir1.html
cp	http://linuxcommand.org/man_pages/cp1.html
xxd	http://linuxcommand.org/man_pages/xxd1.html
file	http://linuxcommand.org/man_pages/file1.html
mv	http://linuxcommand.org/man_pages/mv1.html
gzip	http://linuxcommand.org/man_pages/gzip1.html
bzip2	http://linuxcommand.org/man_pages/bzip21.html
tar	http://linuxcommand.org/man_pages/tar1.html
echo	http://linuxcommand.org/man_pages/echo1.html
nc	http://linuxcommand.org/man_pages/nc1.html
openssl	http://linuxcommand.org/man_pages/openssl1.html