Low 3.7Published Mar 27, 2026

CVE-2026-27860If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication.

Updated under an hour ago (Oct 27, 2026, 10:50 PM ET)

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It affects Open-Xchange GmbH OX Dovecot Pro and 2 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Open-Xchange GmbH OX Dovecot Pro

Exploited in the last 30 days

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: 3.7 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Weakness (CWE): CWE-90
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: OX
NVD analysis: Analyzed
Record last updated: Mar 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Open-Xchange GmbH OX Dovecot Pro open_xchange:ox_dovecot_pro (from the name)	through 3.1.0; through 2.4.0	CNA record
dovecot dovecot dovecot:dovecot	before 2.4.3	NVD
open-xchange dovecot open-xchange:dovecot	before 3.1.4	NVD

References

References

https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.