April 20, 2026 · Applied Cybernetics Group
CVE-2025-48700 — Synacor Zimbra Collaboration Suite (ZCS)
Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability
- Added to KEV
2026-04-20- Federal due date
2026-04-23- Vendor
- Synacor
- Product
- Zimbra Collaboration Suite (ZCS)
- EPSS
- 95.3th percentile (score 0.182, as of
2026-06-08) - NVD CVSS v3.1
- —
- Ransomware use
- Unknown
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2025-48700
CISA short description
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.