An XSS vulnerability exists in the Webmail component of Zimbra Collaboration Suite before 8.8.15 Patch 11. It allows an attacker to inject executable JavaScript into the account name of a user's profile. The injected code can be reflected and executed when changing an e-mail signature.

Zimbra before 8.8.15 Patch 10 and 9.x before 9.0.0 Patch 3 allows remote code execution via an avatar file. There is potential abuse of /service/upload servlet in the webmail subsystem. A user can upload executable files (exe,sh,bat,jar) in the Contact section of the mailbox as an avatar image for a contact. A user will receive a "Corrupt File" error, but the file is still uploaded and stored locally in /opt/zimbra/data/tmp/upload/, leaving it open to possible remote execution.

An issue was discovered in Zimbra Collaboration Suite (ZCS) before 8.8.15 Patch 7. When grantors revoked a shared calendar in Outlook, the calendar stayed mounted and accessible.

Zimbra Collaboration Suite (ZCS) before 8.8.15 Patch 7 allows SSRF when WebEx zimlet is installed and zimlet JSP is enabled.