CVE-2026-27860
Fixed in a distro release EPSS <1%CVSS 3.7
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.
Products: Open-Xchange GmbH OX Dovecot Pro
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.23 | dovecot | 2.4.3-r0 |
| Alpine 3.24 | dovecot | 2.4.3-r0 |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u4 |
| Debian 14 | dovecot | 1:2.4.3+dfsg1-1 |
| SUSE Linux Enterprise Server 16.0 | dovecot24 | 2.4.3-160000.1.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | dovecot24 | 2.4.3-160000.1.1 |
| Ubuntu 22.04 LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.7 |
| Ubuntu 24.04 LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.3 |
| Ubuntu 25.10 | dovecot | 1:2.4.1+dfsg1-5ubuntu4.1 |
| openSUSE Leap 16.0 | dovecot24 | 2.4.3-160000.1.1 |
| openSUSE Tumbleweed | dovecot24 | 2.4.3-1.1 |