An issue was discovered in Zimbra Collaboration (ZCS) 10.1.x before 10.1.1, 10.0.x before 10.0.9, 9.0.0 before Patch 41, and 8.8.15 before Patch 46. It allows authenticated users to exploit Server-Side Request Forgery (SSRF) due to improper input sanitization and misconfigured domain whitelisting. This issue permits unauthorized HTTP requests to be sent to internal services, which can lead to Remote Code Execution (RCE) by chaining Command Injection within the internal service. When combined with existing XSS vulnerabilities, this SSRF issue can further facilitate Remote Code Execution (RCE).