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I SHALL DEVOUR YOUR HEART AND FEAST ON YOUR SOUL (so don't bug me).


Nov
11
awarded  Enlightened
Nov
11
awarded  Good Answer
Nov
11
awarded  Enlightened
Nov
10
comment How bad is it to truncate a hash?
It is possible to define quite contrived hash functions that show how resistances to preimages, second preimages and collisions are distinct concepts. However, if you resist collisions then you resist second preimages at least as well (though you normally expect a much better resistance for second preimages than for collisions).
Nov
10
awarded  Nice Answer
Nov
10
comment How bad is it to truncate a hash?
@NWard: for a collision, you challenge the attacker with finding two distinct inputs that hash to the same value. For a second preimage, you issue the same challenge with the additional constraint that you fix one of the two messages that are to collide. (So it makes sense that finding a second preimage is harder than finding a collision.)
Nov
10
answered How bad is it to truncate a hash?
Nov
10
comment How can I check the integrity of the downloaded files?
"Integrity" does not mean "the file is nice and innocuous". Integrity is about making sure that a given file is exactly the same as it was at its source. It says nothing about the trustworthiness of the source; only that the file was not altered in transit.
Nov
10
answered Does OpenSSL have stat for read change cipher spec (SSL3_ST_CR_CHANGE_A)
Nov
9
revised What is the impact of RSA key's size on CPU load?
edited tags
Nov
9
answered What is the impact of RSA key's size on CPU load?
Nov
9
revised Is email encryption, as claimed by ProtonMail, possible?
Improved title and wording
Nov
9
revised Is email encryption, as claimed by ProtonMail, possible?
added 689 characters in body
Nov
9
answered Is email encryption, as claimed by ProtonMail, possible?
Nov
9
answered Using Diffie-Hellman to verify SSL Certificate?
Nov
9
comment Avast https scanning
A tool that does a MitM can remove the Public-Key-Pins headers to prevent pinning from happening, or, alternatively, register its own fake certificates as pins. However, it can be expected that things will break for servers for which pinning was active before installation of Avast. Conceptually, Avast could try to empty the current cache of pinned keys upon installation (or deactivate pinning altogether), but I am not sure there is an API for that; I don't know if Avast bothers doing it.
Nov
9
comment Is publishing CRLs over HTTP a potential vulnerability?
A CRL contains a field called thisUpdate that documents its age. It also contains a (theoretically optional, but in practice always there) field called nextUpdate that specifies a date at which a newer CRL will be available; all implementations use nextUpdate as a CRL expiration date.
Nov
9
awarded  Nice Answer
Nov
8
answered Telnet and vpn - protected or not
Nov
8
answered Is publishing CRLs over HTTP a potential vulnerability?