Zimbra MTA 10.1.16/10.1.21 LPE via Postfix Sudo Policy
CVE-2026-50057 Published on October 23, 2026
Zimbra Collaboration Suite Local Privilege Escalation via Unrestricted Postfix Sudo Permissions
A local privilege escalation vulnerability in the Zimbra Collaboration Suite (ZCS) MTA package allows the Unix zimbra account to execute arbitrary commands as root. The installed sudo policy permits passwordless root execution of Postfix administration commands without restricting their arguments. An attacker can select a zimbra-controlled daemon_directory in the Postfix configuration and invoke postfix set-permissions, causing Postfix to execute the attacker's post-install program as root. The Postfix configuration directory is also writable by zimbra, so restricting postconf alone does not remove the execution path. Exploitation requires local command execution as zimbra on an MTA node. ZCS 10.1.16 and 10.1.21 are affected.
Vulnerability Analysis
CVE-2026-50057 can be exploited with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
Incorrect Permission Assignment for Critical Resource
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors. When a resource is given a permissions setting that provides access to a wider range of actors than required, it could lead to the exposure of sensitive information, or the modification of that resource by unintended parties. This is especially dangerous when the resource is related to program configuration, execution or sensitive user data.
Products Associated with CVE-2026-50057
Want to know whenever a new CVE is published for Zimbra Collaboration Suite? stack.watch will email you.
Affected Versions
Zimbra Collaboration Suite:- Before and including 10.1.21 is affected.