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    CVE-2026-24031

    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.

    Published:Mar 27, 2026
    Last Modified:Jun 30, 2026
    EPS:Mar 27, 2026
    EPSS Score:0.00294
    CVSS Score:7.7

    Affected Products

    Vendor
    Dovecot
    Product
    Dovecot
    Vendor
    Open-xchange
    Product
    Dovecot
    Vendor
    Open-xchange
    Product
    Ox Dovecot Pro

    Exploits

    https://github.com/aramosf/CVE-2026-24031

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    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High