CVE-2025-48700: Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability

Added to the CISA Known Exploited Vulnerabilities catalog on 20 Apr 2026. Vendor: Synacor. Product: Zimbra Collaboration Suite (ZCS).

Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that could allow attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (due 23 Apr 2026)