PT-2026-28368 · Dovecot+2 · Dovecot+2

Cookiejack15 · Published 2026-01-01 · Updated 2026-04-16 · CVE-2026-27860

Positive Technologies (AI Summary)

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Name of the Vulnerable Software and Affected Versions Dovecot versions prior to 2.4.3

Description If the auth username chars setting is empty, an attacker can inject arbitrary LDAP filters into Dovecot's LDAP authentication process. This can bypass restrictions and allow probing of the LDAP structure. No publicly available exploits are known.

Recommendations Do not clear out the auth username chars setting. Install version 2.4.3 or later.

Fix

Weakness Enumeration

CWE-90

Related Identifiers

CVE-2026-27860

OPENSUSE-SU-2026:10442-1

OPENSUSE-SU-2026:20554-1

SUSE-SU-2026:21208-1

USN-8136-1

Affected Products

Dovecot

Linuxmint

Ubuntu

References · 46

• https://osv.dev/vulnerability/openSUSE-SU-2026:10442-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-59028 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-24031 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-27860 · Security Note
• https://osv.dev/vulnerability/SUSE-SU-2026:21208-1 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-27860 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-27859 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-59031 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-8136-1 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2026-27860 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:20554-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-27858 · Vendor Advisory
• https://osv.dev/vulnerability/USN-8136-1 · Vendor Advisory
• https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-27860 · Vendor Advisory