Scyther cannot find attack

[gilcu3]

The following protocol msc.pdf is insecure. Its corresponding Scyther model is shown below:

protocol DY2(I, R) {

	role I {

		fresh ni: Nonce;

		send_1(I, R, {I, {ni}pk(R)}pk(R) );

		recv_2(R, I, {R, {ni}pk(I)}pk(I) );	

		claim_3(I, Secret, ni);

}


	role R {

		var ni: Nonce;
	
		recv_1(I, R, {I, {ni}pk(R)}pk(R) );

		send_2(R, I, {R, {ni}pk(I)}pk(I) );

	}

}

The attack is attack.pdf. It is a type flaw attack, but no matter how I set the options in Scyther, it says the protocol is "Ok".

[cascremers]

Thanks for the report, we'll look into it.

[cascremers]

P.s. could you please add information on the version of Scyther you used (detailed version number, github commit if possible, and details of the operating system you are using).

[gilcu3]

OS: Archlinux
Scyther : v1.1.3 (installed from http://www.cs.ox.ac.uk/people/cas.cremers/downloads/scyther/scyther-linux-v1.1.3.tgz)

[GOKULKUMAR-2004]

please tell me the is there any syntax error in sycther tool ????