CVE-2026-27860

If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. This leads to potentially bypassing restrictions and allows probing of LDAP structure. Do not clear out auth_username_chars, or install fixed version. No publicly available exploits are known.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

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:::*

History

26 Oct 2026, 00:10

Type	Values Removed	Values Added
Summary		(es) Si auth_username_chars está vacío, es posible inyectar un filtro LDAP arbitrario en la autenticación LDAP de Dovecot. Esto puede llevar a eludir restricciones y permite el sondeo de la estructura LDAP. No vacíe auth_username_chars, o instale la versión corregida. No se conocen exploits disponibles públicamente.

Information

Published : 2026-03-27 09:16

Updated : 2026-10-26 00:10

NVD link : CVE-2026-27860

Mitre link : CVE-2026-27860

CVE.ORG link : CVE-2026-27860

JSON object : View

Products Affected

open-xchange

dovecot

dovecot

dovecot

CWE

CWE-90

Improper Neutralization of Special Elements used in an LDAP Query ('LDAP Injection')

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