Risky Bulletin: Western cyber agencies warn of Russian hacks of Zimbra servers

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Cybersecurity and intelligence agencies from multiple Western countries have issued joint security advisories on Thursday warning of a major Russian hacking campaign that's targeting Zimbra email servers.

The attacks have been going on since last year. The zero-day, tracked as CVE-2025-66376, was patched in November but attacks have been traced back to at least July.

The zero-day itself is…