xxyopen Novel-Plus books sql injection

A vulnerability classified as critical has been found in xxyopen Novel-Plus 3.5.0. This affects an unknown part of the file /api/front/search/books. The manipulation of the argument sort leads to sql injection. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.