Cyber Apocalypse 2023
Extraterrestrial persistence
Solved by : thewhiteh4t
- A bash script is given which installs a systemd service
- one of the lines contains an
echocommand :
echo -e "W1VuaXRdCkRlc2NyaXB0aW9uPUhUQnt0aDNzM180bDEzblNfNHIzX3MwMDAwMF9iNHMxY30KQWZ0ZXI9bmV0d29yay50YXJnZXQgbmV0d29yay1vbmxpbmUudGFyZ2V0CgpbU2VydmljZV0KVHlwZT1vbmVzaG90ClJlbWFpbkFmdGVyRXhpdD15ZXMKCkV4ZWNTdGFydD0vdXNyL2xvY2FsL2Jpbi9zZXJ2aWNlCkV4ZWNTdG9wPS91c3IvbG9jYWwvYmluL3NlcnZpY2UKCltJbnN0YWxsXQpXYW50ZWRCeT1tdWx0aS11c2VyLnRhcmdldA=="|base64 --decode > /usr/lib/systemd/system/service.service
- Decoding the base64 string gives us the flag
HTB{th3s3_4l13nS_4r3_s00000_b4s1c}