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Is SHA-1 insecure?
Actually SHA-1 has been “officially insecure” for a longer time, since an attack method was published in 2011. The 2017 collisions was just the first known case of actually running the attack.
Is HMAC SHA-1 insecure?
Security of the HMAC OTP algorithm is not affected because HMAC was designed so that collisions in the hash function would not produce forgeries in HMAC. No flaws have been identified in HMAC-OTP. As described above, the use of SHA-1 introduces no known vulnerabilities into HMAC-OTP.
Which is faster MD5 or SHA-1?
SHA-1 is fastest hashing function with ~587.9 ms per 1M operations for short strings and 881.7 ms per 1M for longer strings. MD5 is 7.6% slower than SHA-1 for short strings and 1.3% for longer strings. SHA-256 is 15.5% slower than SHA-1 for short strings and 23.4% for longer strings.
Is there any proof that SHA1 is insecure?
I read that, in February 2017, a SHA1 collision was calculated for the first time. This, and earlier theoretical proof, means that SHA1 is officially cryptographicaly insecure.
What are the chances of a real SHA1 exploit?
This, and earlier theoretical proof, means that SHA1 is officially cryptographicaly insecure. But, when using SHA1 in a protocol (SAML assertions in my case), both the protocol dictates a certain message format and the information in the message has to be meaningful to create a real collision exploit.
Which is better SHA-1 or SHA-256?
If you’re asking the question because you think there might be some issue in “mixing” SHA-1 and SHA-256 — so far as I know, there is no reason to be concerned about that in this scenario. Would there be much performance impact if we use diffie-hellman-group-exchange-sha256 and hmac-sha2-256 combination.
Is there a structural weakness in SHA-1?
Moreover, while a structural weakness is known in SHA-1, that allows lowering the cost of the collision attack from 2 80 to 2 63, making it merely “very expensive”, no such weakness is known that would help for second preimages.