CVE-2020-7796
Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery Vulnerability
What the flaw is
Synacor Zimbra Collaboration Suite (ZCS) contains a server-side request forgery vulnerability if WebEx zimlet installed and zimlet JSP is enabled.
Description as published by CISA. We have not independently reproduced it.
What CISA requires
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
This deadline is binding on US federal civilian agencies under BOD 22-01. It is not a legal deadline for anyone else, but it is a useful urgency signal — CISA sets it by how actively the flaw is being used, not by CVSS.
Public exploit code
4 public repositories referencing this CVE have been catalogued on GitHub. Treat this as a strong signal to prioritise patching, not as a verified working exploit — many such repositories are scanners, write-ups or forks rather than functional code.
Vendor advisories
Primary sources
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Source: CISA KEV catalog · last verified July 31, 2026. Rebuilt automatically twice a day.