CVE-2026-33606

dovecot: Dovecot: Unauthorized mailbox modification via dsync command injection

Published Aug 28, 2026 CVSS 3.1 · 4.8 Medium EPSS < 1% KEV · Not listed
Description
Mail content stored by a user can be crafted so that it is interpreted as dsync protocol commands when an administrator later runs dsync with the stream protocol, for example during a migration. Injected commands can modify mailbox state on the destination during migration or replication, including internal mailbox attributes that a user should not be able to set directly. It can also cause dsync errors. Avoid running dsync with the stream protocol on mailboxes with untrusted content. Update to non-vulnerable version. No publicly available exploits are known.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4873-1 dovecot security update
Debian DSA Debian DSA DSA-6526-1 dovecot security update
History
Type Values Removed Values Added
First Time appeared Open-xchange
Open-xchange ox Dovecot Ce
Open-xchange ox Dovecot Pro
Vendors & Products Open-xchange
Open-xchange ox Dovecot Ce
Open-xchange ox Dovecot Pro
Type Values Removed Values Added
Title Mail Content Can Be Treated as Dsync Commands During Migration Leading to Unintended Attribute Changes dovecot: Dovecot: Unauthorized mailbox modification via dsync command injection
Weaknesses CWE-78
References
Metrics threat_severity

None

threat_severity

Moderate

Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
Title Mail Content Can Be Treated as Dsync Commands During Migration Leading to Unintended Attribute Changes
Type Values Removed Values Added
Description Mail content stored by a user can be crafted so that it is interpreted as dsync protocol commands when an administrator later runs dsync with the stream protocol, for example during a migration. Injected commands can modify mailbox state on the destination during migration or replication, including internal mailbox attributes that a user should not be able to set directly. It can also cause dsync errors. Avoid running dsync with the stream protocol on mailboxes with untrusted content. Update to non-vulnerable version. No publicly available exploits are known.
Weaknesses CWE-93
References
Metrics cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
OX
Published
Updated
Aug 28, 2026, 3:55 PM
Reserved
Mar 23, 2026, 12:58 PM
Status
Deferred
Published
Aug 28, 2026, 12:16 PM
Modified
Sep 3, 2026, 6:13 PM
Severity
Moderate
Public date
Aug 28, 2026, 10:12 AM