AWS ENDS SSE-C ENCRYPTION, AND A RANSOMWARE VECTOR

Summary from the TLDR InfoSec newsletter

AWS will end support for AWS SSE-C as an encryption option for S3, following its discovery in ransomware campaigns. SSE-C was a rarely used encryption method for S3 that allowed customers to supply an encryption key for use in S3 API requests. This was useful for ransomware operators because AWS never had access to the key, and it was quieter than alternative methods like KMS. Organizations can use KMS with customer-managed keys (CMK) or client-side encryption to replace the functionality.