Zimbra Collaboration
Hackers breached over 270 Zimbra servers in ongoing attacks
Threat actors have already compromised over 270 Zimbra instances in remote code execution attacks targeting a high-severity Zimbra Collaboration Suite (ZCS) vulnerability. The ZCS email and collaboration suite is used by hundreds of millions of people and organizations, including thousands of businesses and hundreds of government agencies worldwide. Synacor patched the security flaw (tracked as CVE-2026-73570), […]
CISA orders urgent patching of actively exploited Zimbra flaw
The Cybersecurity and Infrastructure Security Agency (CISA) has ordered U.S. government agencies to patch an actively exploited vulnerability in Zimbra Collaboration Suite (ZCS) within three days. The Zimbra security team patched the security flaw (tracked as CVE-2026-73570) in version 10.1.20, released on July 20. Successful exploitation allows unauthenticated attackers to gain remote code execution by exploiting a […]
Critical Zimbra RCE flaw now actively exploited in attacks
CERT Polska, the Polish Computer Emergency Response Team (CERT), warned that attackers have begun exploiting a critical vulnerability in Zimbra Collaboration Suite (ZCS). ZCS is a popular email and collaboration software suite used by hundreds of millions of people and organizations worldwide, including thousands of businesses and hundreds of government agencies. The Zimbra security team released […]
Over 10,000 Zimbra servers vulnerable to ongoing XSS attacks
Over 10,000 Zimbra Collaboration Suite (ZCS) instances exposed online are vulnerable to ongoing attacks exploiting a cross-site scripting (XSS) security flaw, according to nonprofit security organization Shadowserver. Zimbra is a popular email and collaboration software suite used by hundreds of millions of people worldwide, including hundreds of government agencies and thousands of businesses. The vulnerability (tracked as CVE-2025-48700) […]
Russian hackers exploit Zimbra flaw in Ukrainian govt attacks
Hackers part of APT28, a state-backed threat group linked to Russia’s military intelligence service (GRU), are exploiting a Zimbra Collaboration Suite (ZCS) vulnerability in attacks targeting Ukrainian government entities. This high-severity security flaw (tracked as CVE-2025-66376 and patched in early November) stems from a stored cross-site scripting (XSS) that unauthenticated attackers can exploit to gain remote code execution (RCE) […]
CISA orders feds to patch Zimbra XSS flaw exploited in attacks
CISA has ordered U.S. government agencies to secure their servers against an actively exploited vulnerability in the Zimbra Collaboration Suite (ZCS). Zimbra is a very popular email and collaboration software suite used by hundreds of millions of people worldwide, including thousands of businesses and hundreds of government agencies. Tracked as CVE-2025-66376 and patched in early November, this high-severity security […]
CISA confirms active exploitation of four enterprise software bugs
The Cybersecurity and Infrastructure Security Agency (CISA) in the U.S. warned of active exploitation of four vulnerabilities impacting enterprise software from Versa and Zimbra, the Vite frontend tooling framework, and the Prettier code formatter. The security issues have been added to CISA’s KEV (Known Exploited Vulnerabilities) catalog, indicating that the agency has evidence that hackers are exploiting them in the […]