Zimbra Collaboration Suite zero-click command injection CVE-2026-73570 exploited to take over email servers
Microsoft Threat Intelligence reports active exploitation of CVE-2026-73570, a command injection flaw in Zimbra Collaboration Suite that allows unauthenticated, zero-click compromise of internet-facing email servers. Attackers deployed webshells, escalated privileges, harvested authentication secrets and staged mailbox data across organiz…