What’s Vulnerable › Vulnerabilities

CVE-2019-9621: Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (SSRF) Vulnerability

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2025-07-07
• EPSS: 81.0% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2019-04-30 · updated 2026-06-17
• Weakness: CWE-918

Description

Zimbra Collaboration Suite before 8.6 patch 13, 8.7.x before 8.7.11 patch 10, and 8.8.x before 8.8.10 patch 7 or 8.8.x before 8.8.11 patch 3 allows SSRF via the ProxyServlet component.

Affected products

• Zimbra Collaboration: before 8.6.0; from 8.7.0 before 8.7.11; from 8.8.0 before 8.8.9; 8.6.0, 8.6.0-patch1, 8.6.0-patch10, 8.6.0-patch11, 8.6.0-patch12, 8.6.0-patch2 (+39) — fixed in 8.6.0, 8.7.11, 8.8.9

How to fix

Upgrade to a fixed version: Zimbra Collaboration 8.6.0, 8.7.11, 8.8.9. Check the vendor advisory for mitigations.

References

• http://packetstormsecurity.com/files/152487/Zimbra-Collaboration-Autodiscover-Servlet-XXE-ProxyServlet-SSRF.html
• http://packetstormsecurity.com/files/153190/Zimbra-XML-Injection-Server-Side-Request-Forgery.html
• http://www.rapid7.com/db/modules/exploit/linux/http/zimbra_xxe_rce
• https://blog.tint0.com/2019/03/a-saga-of-code-executions-on-zimbra.html
• https://blog.zimbra.com/2019/03/9826/
• https://bugzilla.zimbra.com/show_bug.cgi?id=109127
• https://wiki.zimbra.com/wiki/Security_Center
• https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
• https://www.exploit-db.com/exploits/46693/
• http://packetstormsecurity.com/files/152487/Zimbra-Collaboration-Autodiscover-Servlet-XXE-ProxyServlet-SSRF.html
• http://packetstormsecurity.com/files/153190/Zimbra-XML-Injection-Server-Side-Request-Forgery.html
• http://www.rapid7.com/db/modules/exploit/linux/http/zimbra_xxe_rce

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