Errors in log

Hi! Today i has a look in logs and find some errors. Everithing works good. I want to do anithing?

Thanks.

2017-06-24 19:37:10  WARN: Unknown device - 002000040020f00 (172.104.140.171)
2017-06-24 19:37:10  WARN: [EE9F0398] error - Adjusted frame length (0) is less than lengthFieldEndOffset: 5 - CorruptedFrameException (...)
2017-06-24 19:37:10  INFO: [EE9F0398] disconnected
2017-06-24 19:37:10  WARN: [EE9F0398] error - Adjusted frame length (0) is less than lengthFieldEndOffset: 5 - CorruptedFrameException (... < MainEventHandler:115 < *:1
04 < ... < ExtendedObjectDecoder:52 < ... < GeocoderHandler:49 < ...)
2017-06-24 19:37:10  INFO: [AD3BB0DA] connected
2017-06-24 19:37:10 DEBUG: [AD3BB0DA: 5094 < 172.104.140.171] HEX: 4a524d4900024b
2017-06-24 19:37:11  INFO: [AD3BB0DA] disconnected
2017-06-24 19:37:11  INFO: [BD590419] connected
2017-06-24 19:37:11 DEBUG: [BD590419: 5094 < 172.104.140.171] HEX: 010000fdcefa0bb0a00000004d4d53140000000000000000000000000000001200000001000300f0f0f0f00b0004001c00030
04e00530050006c0061007900650072002f0039002e00002e00002e020039003800003b0020007b00000000004100410000002d0000410000002d0000006100002d00410041000041002d0000000000410000410
041000041004100007d000000e06ddf5f
2017-06-24 19:37:13  INFO: [BD590419] disconnected
2017-06-24 19:37:13  INFO: [A92EDB92] connected
2017-06-24 19:37:13 DEBUG: [A92EDB92: 5094 < 172.104.140.171] HEX: 005a0000010000000136012c000008007fff7f08000000010020003a00000000000000000000000000000004e600000001000
000000000000028434f4e4e4543545f444154413d28434f4d4d414e443d76657273696f6e2929
2017-06-24 19:37:13  WARN: [A92EDB92] error - Adjusted frame length (1) is less than lengthFieldEndOffset: 5 - CorruptedFrameException (...)
2017-06-24 19:37:13  INFO: [A92EDB92] disconnected
2017-06-24 19:37:13  INFO: [68D77922] connected
2017-06-24 19:37:13 DEBUG: [68D77922: 5094 < 172.104.140.171] HEX: 000300010000000000000002000000000f00
2017-06-24 19:37:14  INFO: [68D77922] disconnected
2017-06-24 19:37:14  INFO: [AAAE3E4D] connected
2017-06-24 19:37:14 DEBUG: [AAAE3E4D: 5094 < 172.104.140.171] HEX: 47494f500100010024000000000000000100000001000000060000006162636465660000040000006765740000000000
2017-06-24 19:37:16  INFO: [AAAE3E4D] disconnected
2017-06-24 19:37:16  INFO: [48DDA118] connected
2017-06-24 19:37:16 DEBUG: [48DDA118: 5094 < 172.104.140.171] HEX: 009c00011a2b3c4d00010000010000000000000100000001ffff00016e6f6e650000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000000000000000000000000000000000006265000000000000000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000
2017-06-24 19:37:17  INFO: [48DDA118] disconnected
2017-06-24 19:50:01 DEBUG: [E0CC9943: 5084 < 212.47.2

Something or someone is sending invalid messages to your server. I don't think it's anything to worry about, unless it happens all the time.