Hackers Have Breached 270+ Zimbra Servers — What Mail Hosting Operators Should Do Now
An active attack campaign has compromised more than 270 Zimbra Collaboration Suite (ZCS) instances through a high-severity remote code execution (RCE) vulnerability, according to reporting from BleepingComputer. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added the flaw to its Known Exploited Vulnerabilities catalog and ordered Federal Civilian Executive Branch agencies to patch their systems by August 24. Despite the noise, at least 8,200 unpatched Zimbra instances reportedly remain reachable from the public internet. For the hosting community — sysadmins running self-managed mail on VPS boxes, MSPs maintaining customer email stacks, agencies and universities that standardized on Zimbra years ago — this is not abstract news. It is an operational incident with a live clock attached, and the window for clean remediation narrows every day the campaign continues. Related ServerSpan guide: Take Back Your Privacy: The Complete Guide to Migrating from Gmail to a Se...