MISP Dashboard Template ACL Bypass Due to VARCHAR-to-Integer Type Coercion in Permission Flag Comparison

Affected versions of MISP incorrectly filter dashboard templates that are restricted to a specific permission flag. DashboardsController::listTemplates() allowed a template when either:  - its restrict_to_permission_flag matched one of the current user’s permission flags, or  - restrict_to_permission_flag equaled integer 0 However, restrict_to_permission_flag is a varchar. MySQL therefore performed numeric coercion when comparing the column against integer 0. Strings such as perm_site_admin convert numerically to zero, making expressions such as perm_site_admin = 0 evaluate true and causing the “unrestricted” branch to match permission-restricted templates as well. Version affected: ≤2.5.45