CVE-2026-27860
Low
Description
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.
SeverityLow
CVSS3.7
Exploit probability—
ProductDovecot
PublishedMar 27, 2026
First seenMar 27, 2026
Weakness typeCWE-90CWE-90
How to fix
Update
- dovecot dovecot2.4.3 or later
- open-xchange dovecot3.1.4 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| dovecot dovecot | v < 2.4.3 | 2.4.3 |
| open-xchange dovecot | v < 3.1.4 | 3.1.4 |
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