# CVE-2026-50057: Zimbra Collaboration Suite MTA local privilege escalation

Source: https://junglewise.ai/threats/cve-2026-50057-a-local-privilege-escalation-vulnerability-in-the-zimbra  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-23. Updated: 2026-10-23  
License: CC BY 4.0 with a link back

CVE-2026-50057 · Severity: high · CVSS 7.8 · Published 2026-10-23

Zimbra Collaboration Suite (ZCS) MTA, a self-hosted email and collaboration platform, contains a local privilege escalation flaw in the Postfix mail transfer agent. An attacker with local command execution as the zimbra user can exploit a misconfigured sudo policy to execute arbitrary commands as root, gaining complete control of the mail server and access to all email data and credentials stored on it.

Technologies: [Zimbra Collaboration Suite](https://junglewise.ai/threats/technologies/collaboration). Vendors: [Zimbra](https://junglewise.ai/threats/vendors/zimbra).

## Quick answers

**Is CVE-2026-50057 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-50057 being exploited in the wild.

**How severe is CVE-2026-50057?** High severity, with a CVSS score of 7.8, published 23 October 2026.

**Which products and versions are affected?** Zimbra Collaboration Suite 10.1.16, 10.1.21.

**Is there a fix for CVE-2026-50057?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-50057 attacked?** It is attacked with local access, in a hosted service.

**Am I affected by CVE-2026-50057?** Check whether you run Zimbra Collaboration Suite at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the sudo policy that allows the zimbra account to run Postfix administration commands (postfix set-permissions) without password and without argument restrictions. An attacker can manipulate the Postfix configuration (which is writable by zimbra) to point to an attacker-controlled daemon_directory, then invoke postfix set-permissions to execute a malicious post-install script as root. Exploitation requires prior local command execution as the zimbra user on an MTA node.

## Affected products

- Zimbra Collaboration Suite 10.1.16, 10.1.21

## Timeline

- 2026-10-23: disclosed

## References

- [https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories](https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories)
- [https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/](https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/)

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