CVE-2026-55843: Snipe-IT has an Improper Privilege Management issue

The update() method in UsersController passes the permission request field unconditionally to NormalizePermissionsPayloadAction, which returns an empty array when the field is absent. The result is passed to PreserveUnauthorizedPrivilegedPermissionsAction, which selectively restores only the superuser key (when the editor is not a superuser) and the admin key (when the editor is neither admin nor superuser). All other permissions — including the admin flag itself when the editing user is an admin — are discarded and $user->permissions is overwritten with the sparse result.

The canEditAuthFields gate permits admins to update other non-superuser accounts (including other admins). When an admin sends a PUT /users/{id} request for another admin without including the permission field, the target’s admin flag and all granular permissions are permanently destroyed. The target loses administrative access entirely with no error, warning, or out-of-band notification.

A secondary, lower-impact path exists for non-admin users holding the users.edit permission: they may target regular (non-admin, non-superuser) accounts and wipe all granular permissions in the same way.