March 15, 2025 By Bill Toulas
Security researcher Yohanes Nugroho has released a decryptor for the Linux variant of Akira ransomware, which utilizes GPU power to retrieve the decryption key and unlock files for free.
Nugroho developed the decryptor after being asked for help from a friend, deeming the encrypted system solvable within a week, based on how Akira generates encryption keys using timestamps.
The project ended up taking three weeks due to unforeseen complexities, and the researcher spent $1,200 on GPU resources to crack the encryption key, but eventually, he succeeded.
Using GPUs to brute force keys
Nugroho's decryptor does not work like a traditional decryption tool where users supply a key to unlock their files.
Instead, it brute-forces encryption keys (unique for each file) by exploiting the fact that the Akira encryptor generates its encryption keys based on the current time (in nanoseconds) as a seed.
