Tens of thousands of HTTPS-protected websites, mail servers, and other widely used Internet services are vulnerable to a new attack that lets eavesdroppers read and modify data passing through encrypted connections.
The weakness is the result of export restrictions the US government mandated in the 1990s on US developers who wanted their software to be used abroad. The regime was established by the Clinton administration so the FBI and other agencies could break the encryption used by foreign entities. Attackers with the ability to monitor the connection between an end user and a Diffie-Hellman-enabled server that supports the export cipher can inject a special payload into the traffic that downgrades encrypted connections to use extremely weak 512-bit key material.
Read about it in Threat Attack, here.
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