Zimbra Collaboration Suite Local Privilege Escalation via Unrestricted Postfix Sudo Permissions
Summary
| CVE | CVE-2026-50057 |
|---|---|
| State | PUBLISHED |
| Assigner | rapid7 |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-23 14:17:53 UTC |
| Updated | 2026-10-24 04:18:18 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Problem Types: CWE-732 | CWE-732 CWE-732 Incorrect Permission Assignment for Critical Resource
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | CVSS | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Zimbra | Zimbra Collaboration Suite | affected 10.1.21 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1 | [email protected] | www.rapid7.com | |
| wiki.zimbra.com/wiki/Zimbra_Security_Advisories | [email protected] | wiki.zimbra.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7 (en)
There are currently no legacy QID mappings associated with this CVE.