Date Added: Dec 2009
In the challenge of ensuring the correct behaviour of legacy implementations of security protocols, a formally-based approach is presented to design and implement monitors that stop insecure protocol runs executed by such legacy implementations, without the need of their source code. The authors validate the approach at a case study about monitoring several SSL legacy implementations. Recently, a security bug has been found in the widely deployed OpenSSL client; their case study shows that their monitor correctly stops the protocol runs otherwise allowed by the faulty OpenSSL client. Moreover, their monitoring approach allowed one to detect a new aw in another open source SSL client implementation.