CVE-2026-27856

Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm http service port, install fixed version. No publicly available exploits are known.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:dovecot:dovecot::::::::
	cpe:2.3:a:open-xchange:dovecot:::::pro:::*
	cpe:2.3:a:open-xchange:dovecot:::::pro:::*
	cpe:2.3:a:open-xchange:dovecot:::::pro:::*

History

29 Apr 2026, 19:25

Type	Values Removed	Values Added
First Time		Open-xchange Open-xchange dovecot Dovecot Dovecot dovecot
References	~~() https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json -~~	() https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json - Vendor Advisory
CWE		NVD-CWE-Other
CPE		cpe:2.3:a:dovecot:dovecot:::::::: cpe:2.3:a:open-xchange:dovecot:::::pro:::*

27 Mar 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-27 09:16

Updated : 2026-04-29 19:25

NVD link : CVE-2026-27856

Mitre link : CVE-2026-27856

CVE.ORG link : CVE-2026-27856

JSON object : View

Products Affected

open-xchange

dovecot

dovecot

dovecot

CWE

CWE-287

Improper Authentication

NVD-CWE-Other

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