Exploited vulnerability · CISA KEV
Yes. CVE-2019-9621, Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (SSRF) Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 7 Jul 2025, 2260 days after it was published. It affects Synacor Zimbra Collaboration Suite (ZCS). If you run it, CISA's required action is: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Synacor Zimbra Collaboration Suite (ZCS) contains a server-side request forgery (SSRF) vulnerability via the ProxyServlet component.
| Vendor | Synacor (19 exploited CVEs in KEV) |
| Product | Zimbra Collaboration Suite (ZCS) |
| Vulnerability | Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (SSRF) Vulnerability |
| Weakness | CWE-918, CWE-807 |
| Published | 30 Apr 2019 |
| Added to KEV | 7 Jul 2025 |
| Reported by (CNA) | mitre |
Yes. CISA added CVE-2019-9621 to the Known Exploited Vulnerabilities catalog on 7 Jul 2025, which means there is reliable evidence of exploitation in the wild.
CISA does not list known ransomware use for it. That can change, and exploitation alone is reason to fix it first.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Check Synacor's advisory for the fixed versions, and if you can't patch quickly, restrict access to the affected Zimbra Collaboration Suite (ZCS) and watch it for signs of compromise.
Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in July 2025 · Synacor scorecard · act-now radar.
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