3 ms·
This paper is great and contains some really interesting historical examples of backdoored crypto. For example, Lotus Notes 4 circumvented export controls by us
by swordswinger12 12y ago
This paper is great and contains some really interesting historical examples of backdoored crypto. For example, Lotus Notes 4 circumvented export controls by using a 64-bit key but taking the first 24 bits and encrypting them with a public key available to the NSA, thus meeting the 40-bit limit.
- yuhong 12y agoThat 768-bit RSA key is factorable nowadays.
- xnull2guest 12y agoAs is the 64-bit keyspace breakable.
- yuhong 12y agoBut the 768-bit key only has to be factored once.
- deleted 12y ago[deleted]
- PeterWhittaker 12y agoI'm not sure I'm at liberty to cite explicitly another example, but I will allude to it: At the time when only 512-bit-RSA was permitted for general export, export a 1024-bit-RSA based system by ensuring that each time public key encryption is performed, a 512-bit key pair is generated, the wrapped symmetric key included with the payload, and the 512-bit key pair discarded. Removed in later versions, AFAIK, as regulations relaxed, e.g., with the advent of Wassenaar.
- yuhong 12y agoSSL 3.0 and TLS 1.0 did this (with a ServerKeyExchange message), with the limit being 512-bit for 40-bit export cipher suites and 1024-bit for the 56-bit export cipher suites. This is another reason why it is unfortunate that the 56-bit export cipher suites was disabled in OpenSSL in 2006.
- PeterWhittaker 12y agoWow, timely: http://www.washingtonpost.com/blogs/the-switch/wp/2015/03/03/freak-flaw-undermines-security-for-apple-and-google-users-researchers-discover/ http://www.washingtonpost.com/blogs/the-switch/wp/2015/03/03... and https://news.ycombinator.com/item?id=9139273 https://news.ycombinator.com/item?id=9139273