---
id: CVE-2026-50057
title: >-
  Zimbra Collaboration Suite Local Privilege Escalation via Unrestricted Postfix
  Sudo Permissions
summary: >-
  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…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-732
vendor: Zimbra
product: Zimbra Collaboration Suite
affected:
  - collaboration_suite <= 10.1.21
published: '2026-10-23'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T13:33:29.682Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-50057'
references:
  - url: 'https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories'
  - url: >-
      https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/
tags:
  - cve.org
ingestedAt: '2026-10-23T14:28:08.705Z'
---

## Overview

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.

## Affected

- `collaboration_suite <= 10.1.21`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.