Vanilla Tempest
-
Microsoft revokes more than 200 certificates used in fake Teams ransomware campaign
Microsoft said it revoked over 200 code signing certificates used by a group tracked as Vanilla Tempest to sign fake Microsoft Teams installers that delivered the Oyster backdoor and Rhysida ransomware; the company said it detected the activity in late September 2025 and has updated protections to flag the malicious signatures.
