CVE-2026-24031: Dovecot SQL based authentication can be bypassed when auth_u...
Summary
Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by admin. This vulnerability allows bypassing authentication for any user and user enumeration. Do not clear auth_username_chars. If this is not possible, install latest fixed version. No publicly available exploits
Threat Analysis
**Vulnerability ID:** CVE-2026-24031
**CVSS Score:** 7.7 (High)
**Description:** Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by admin. This vulnerability allows bypassing authentication for any user and user enumeration. Do not clear auth_username_chars. If this is not possible, install latest fixed version. No publicly available exploits are known.
**Recommended Mitigations:** - Apply vendor security patches immediately - Review and update security configurations - Monitor systems for signs of compromise - Implement network segmentation where applicable