A local privilege escalation vulnerability in the optional dnscache package of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to access files with root privileges. The passwordless sudo policy permits arbitrary arguments to zmunbound, whose wrapper forwards them to Unbound without restricting the configuration path. An attacker can supply a configuration that retains root privileges and disables the chroot. Include directives expose root-readable file contents through parser errors, while an attacker-selected logfile path creates a root-owned file or appends Unbound log records to an existing file. This can disclose password hashes and private keys and corrupt privileged configuration files, preventing affected services from starting with the modified configuration. The affected configuration is present in ZCS 10.1.16 and 10.1.21 dnscache packages.
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Fixes

Solution

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Workaround

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History

Fri, 23 Oct 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 23 Oct 2026 13:45:00 +0000

Type Values Removed Values Added
Description A local privilege escalation vulnerability in the optional dnscache package of Zimbra Collaboration Suite (ZCS) allows the Unix zimbra account to access files with root privileges. The passwordless sudo policy permits arbitrary arguments to zmunbound, whose wrapper forwards them to Unbound without restricting the configuration path. An attacker can supply a configuration that retains root privileges and disables the chroot. Include directives expose root-readable file contents through parser errors, while an attacker-selected logfile path creates a root-owned file or appends Unbound log records to an existing file. This can disclose password hashes and private keys and corrupt privileged configuration files, preventing affected services from starting with the modified configuration. The affected configuration is present in ZCS 10.1.16 and 10.1.21 dnscache packages.
Title Zimbra Collaboration Suite Local Privilege Escalation via Unrestricted zmunbound Sudo Configuration
Weaknesses CWE-732
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: rapid7

Published:

Updated: 2026-10-23T13:50:34.330Z

Reserved: 2026-09-18T12:22:38.559Z

Link: CVE-2026-93640

cve-icon Vulnrichment

Updated: 2026-10-23T13:50:30.425Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-23T14:17:57.757

Modified: 2026-10-23T16:44:17.950

Link: CVE-2026-93640

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-23T16:30:18Z

Weaknesses