Robuta

https://thehackernews.com/2018/06/free-ransomware-decryption-tools.html
Security researchers have released a free ransomware decryption tool, dubbed ThanatosDecryptor, to help users unlock files encrypted with Thanatos ransomware.
ransomware decryption toolfreethanatosreleased
https://thehackernews.com/2023/12/fbi-takes-down-blackcat-ransomware.html?m=1
U.S. Justice Department disrupts the BlackCat ransomware operation and releases a decryption tool
fbitakesblackcatransomwarereleases
https://securityaffairs.com/159031/cyber-crime/rhysida-ransomware-decryption-tool.html
Researchers discovered a vulnerability in the code of the Rhysida ransomware that allowed them to develop a decryption tool.
expertsreleasedfreedecryptiontool
https://www.tripwire.com/state-of-security/free-decryption-tool-created-for-pylocky-ransomware-family
A researcher has created a free decryption tool which victims of the PyLocky ransomware family can use to recover their affected files.
freedecryptiontoolcreatedransomware
https://www.tripwire.com/state-of-security/free-decryption-tool-released-for-syrk-ransomware
Security researchers have released a decryption tool which victims of Syrk ransomware can use to recover their files for free.
freedecryptiontoolreleasedransomware