July 7, 2025 · Applied Cybernetics Group
CVE-2019-9621 — Synacor Zimbra Collaboration Suite (ZCS)
Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (SSRF) Vulnerability
- Added to KEV
2025-07-07- Federal due date
2025-07-28- Vendor
- Synacor
- Product
- Zimbra Collaboration Suite (ZCS)
- EPSS
- 99.9th percentile (score 0.941, as of
2026-06-08) - NVD CVSS v3.1
- —
- Ransomware use
- Unknown
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2019-9621
CISA short description
Synacor Zimbra Collaboration Suite (ZCS) contains a server-side request forgery (SSRF) vulnerability via the ProxyServlet component.
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.