Forensics, Hard, 500 Points
It gets real sticky when you're walking kernel structs...
I extracted the files from the jelly.zip. It contained a jelly.elf which was 2.5GiB size.
I extracted strings from from jelly.elf
➜ jelly strings jelly.elf > jelly.txt
Then looked for a while and found the line
echo "bitcoin: G9mzcaHrPAZnkfMCgsNrt5Y8VXSfV74E2kNhYeaWgPYCrtNDzZzC" > flag.txt
We know Bitcoin addresses are written base58 and start with 0x80
Decoded the hash
➜ jelly echo G9mzcaHrPAZnkfMCgsNrt5Y8VXSfV74E2kNhYeaWgPYCrtNDzZzC | base58 -d
flag{a70f5c001e67e4c26bf20dc457d43459}