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.
There is a Persistent XSS vulnerability in the briefcase component of Synacor Zimbra Collaboration Suite (ZCS) Zimbra Web Client (ZWC) 8.8.8 before 8.8.8 Patch 7 and 8.8.9 before 8.8.9 Patch 1.
An issue was discovered in Synacor Zimbra Collaboration Suite 8.6.x before 8.6.0 Patch 11, 8.7.x before 8.7.11 Patch 6, 8.8.x before 8.8.8 Patch 9, and 8.8.9 before 8.8.9 Patch 3. Account number enumeration is possible via inconsistent responses for specific types of authentication requests.
ZxChat (aka ZeXtras Chat), as used for zimbra-chat and zimbra-talk in Synacor Zimbra Collaboration Suite 8.7 and 8.8 and in other products, allows XXE attacks, as demonstrated by a crafted XML request to mailboxd.
mailboxd component in Synacor Zimbra Collaboration Suite 8.7.x before 8.7.11p10 has an XML External Entity injection (XXE) vulnerability, as demonstrated by Autodiscover/Autodiscover.xml.