Another option could be a practical attack on 128bit RC4.
But I don't think the fact they're still using it means it hasn't been broken. Historically countries have sacrificed countless soldiers because saving them would have revealed that the enemy crypto-system had been broken.
They don't. They use Suite A, which is an eclectic mix of proprietary algorithms. Firefly/Enhanced Firefly for key exchange (PKI), Joeski (allegedly a pair of algorithms for encrypting and decrypting other ciphers or firmware with the interesting property that encryption algorithm cannot be deduced from the decryption algorithm and vice versa), and a bunch of others. They have different algorithms depending on the specific information channel. Permanent data storage uses one (or perhaps a few), communications traffic uses others, and communications are further split depending on channel bandwidth and presumably long-term classification needs of the data.
They have to recommend Suite B to the government and military in cases where NSA validated hardware can't be used. Examples would be military communications with allies, garden variety agencies that can't afford or can't be trusted with Suite A modules.
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On point 2, NSA still allows the use of AES-256 to protect top secret data: http://en.wikipedia.org/wiki/NSA_Suite_B_Cryptography
Another option could be a practical attack on 128bit RC4.
But I don't think the fact they're still using it means it hasn't been broken. Historically countries have sacrificed countless soldiers because saving them would have revealed that the enemy crypto-system had been broken.
Why is everyone assuming the NSA has to be using their own standards, behind close doors?
They don't. They use Suite A, which is an eclectic mix of proprietary algorithms. Firefly/Enhanced Firefly for key exchange (PKI), Joeski (allegedly a pair of algorithms for encrypting and decrypting other ciphers or firmware with the interesting property that encryption algorithm cannot be deduced from the decryption algorithm and vice versa), and a bunch of others. They have different algorithms depending on the specific information channel. Permanent data storage uses one (or perhaps a few), communications traffic uses others, and communications are further split depending on channel bandwidth and presumably long-term classification needs of the data.
They have to recommend Suite B to the government and military in cases where NSA validated hardware can't be used. Examples would be military communications with allies, garden variety agencies that can't afford or can't be trusted with Suite A modules.