Good afternoon everyone I get a new query regarding a type of attack that our freeswitch servers receive constantly in case someone knows how to block them. These are INVITE or REGISTER requests in which the FROM: field arrives with the ip and port equal to the public interface of the server, so the different protection options that I have tried have not blocked these requests: - IpTables can not filter by the information From the INVITE message. - Fail2Ban is equally limited than IpTables. - ACLs have not resolved to filter these requests. Does anyone know any way to block these requests? I send here a trace with an INVITE message where you can see a request of this type. Thanks and best regards. U 2017/12/14 18:32:55.156886 185.107.94.121:11120 -> 182.30.1.194:5060 INVITE sip:390239297988@ 182.30.1.194:5060;transport=UDP SIP/2.0. Via: SIP/2.0/UDP 122.221.117.131:5060;branch=z9hG4bK-524287-1---xi3qy2kz737ni404. Max-Forwards: 70. Contact: <sip:15714000000@122.221.117.131:5060;transport=UDP>. To: <sip:390239297988@ 182.30.1.194;transport=UDP>. From: <sip:15714000000@ 182.30.1.194;transport=UDP>;tag=hlzg2jcv. Call-ID: KaQqH51mAcFv34qN8cGyv3... CSeq: 1 INVITE. Content-Type: application/sdp. User-Agent: Z 3.14.38765 rv2.8.3. Allow-Events: presence, kpml, talk. Content-Length: 0. . --- El software de antivirus Avast ha analizado este correo electrónico en busca de virus. https://www.avast.com/antivirus