Download binary file and chmod +x binary to execute this file and program will ask for password.
Open binary file with IDA Pro, Go to Strings tab to find some interest string, I see eWFfcmFnZWw= I think this strings is Base64 encode. Go to submit this decode string but not a flag, Next step I go to find Base64 function in this binary file and I found this.
Find next interest strings..and I try samir to base64 encode.
And input this result c2FtaXI= to program.
I think I got a flag ping-pong you pasamir, Go to submit again but It wrong. :(, I try ping-pong It work. LoL