An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient sanitization of HTML content in ICS files. When a user views an e-mail message containing a malicious ICS entry, its embedded JavaScript executes via an ontoggle event inside a <details> tag. This allows an attacker to run arbitrary JavaScript within the victim's session, potentially leading to unauthorized actions such as setting e-mail filters to redirect messages to an attacker-controlled address. As a result, an attacker can perform unauthorized actions on the victim's account, including e-mail redirection and data exfiltration.

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).

The postjournal service in Zimbra Collaboration (ZCS) before 8.8.15 Patch 46, 9 before 9.0.0 Patch 41, 10 before 10.0.9, and 10.1 before 10.1.1 sometimes allows unauthenticated users to execute commands.

An issue in Zimbra Collaboration ZCS v.8.8.15 and v.9.0 allows an attacker to execute arbitrary code via the sfdc_preauth.jsp component.

An issue in Zimbra Collaboration (ZCS) v.8.8.15 and v.9.0 allows a remote attacker to escalate privileges and obtain sensitive information via the password and 2FA parameters.

An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. Remote code execution can occur through ClientUploader by an authenticated admin user. An authenticated admin user can upload files through the ClientUploader utility, and traverse to any other directory for remote code execution.