When binding against a DN during authentication, the reply from 389-ds-base will be different whether the DN exists or not. This can be used by an unauthenticated attacker to check the existence of an entry in the LDAP database.
{
    "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
    "binaries": [
        {
            "binary_name": "389-ds",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        },
        {
            "binary_name": "389-ds-base",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        },
        {
            "binary_name": "389-ds-base-dev",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        },
        {
            "binary_name": "389-ds-base-libs",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        },
        {
            "binary_name": "cockpit-389-ds",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        },
        {
            "binary_name": "python3-lib389",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
        }
    ]
}