Aperi’CTF 2019 - Hello Ducky
Challenge details
| Event | Challenge | Category | Points | Solves |
|---|---|---|---|---|
| Aperi’CTF 2019 | Hello Ducky | Physical | 50 | ??? |
Votre mission est de récupérer le fichier flag.txt situé à la racine du disque C:// du PC “Ducky”. L’exfiltration des données peut se faire à l’aide d’internet ou d’une clé USB classique (montage D:// par default). Le flag respecte le format APRK{…}.
TL;DR
Use xcopy Windows command with ducky script.
Methodology
We need to copy the file “C:\flag.txt” to our USB “D:\” with only a Rubber Ducky HID key:
This key is a USB key which act like a keyboard: once plugged, it will type the payload we want. See this Youtube Video for more explanation about Rubber Ducky.
To complete the challenge, we gonna run a command with “Win + R” (here: GUI + r) and run the command xcopy "C:\flag.txt" "D:\".
Here is the final ducky payload:
DELAY 3000
GUI r
DELAY 1000
STRING xcopy "C:\flag.txt" "D:\"
ENTER
After that, we compiled the script on ducktoolkit.com/encode with FR layout, put the file on the Micro SD using the adapter and plug the Rubber Ducky.
Once plugged, we got a “flag.txt” at the root of our USB: APRK{Th3_PoW3R_oF_dUckY_sCR!PT}.
Flag
APRK{Th3_PoW3R_oF_dUckY_sCR!PT}