CVE-2026-27860
Low · 3.7CVSS
3.7
EPSS
0.3%
Published
Mar 27, 2026
CISA due date
—
The record
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.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| openSUSE:Leap 16.0 | dovecot24 | 0 | 2.4.3-160000.1.1 |
| openSUSE:Tumbleweed | dovecot24 | 0 | 2.4.3-1.1 |
Related vulnerabilities
- CVE-2026-42006 An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. Also affects dovecot24
- CVE-2026-40016 Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to… Also affects dovecot24
- CVE-2026-40020 Attacker can use the IMAP SETACL command to inject the anyone permission to user's… Also affects dovecot24
- CVE-2026-33603 Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake… Also affects dovecot24
- CVE-2026-27851 When safe filter is used with variable expansion, all following pipelines on the same… Also affects dovecot24
- CVE-2026-27858 Attacker can send a specifically crafted message before authentication that causes… Also affects dovecot24
- CVE-2026-27859 A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use… Also affects dovecot24
- CVE-2026-24031 Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by… Also affects dovecot24