https://www.bleepingcomputer.com/news/security/ransomware-data-theft-tool-may-show-a-shift-in-extortion-tactics/

Data exfiltration malware known as Exmatter and previously linked with the BlackMatter ransomware group is now being upgraded with data corruption functionality that may indicate a new tactic that ransomware affiliates might switch to in the future.

The new sample was spotted by malware analysts with the Cyderes Special Operations team during a recent incident response following a BlackCat ransomware attack and later shared with the Stairwell Threat Research team for further analysis (Symantec saw a similar sample deployed in a Noberus ransomware attack).