Cryptanalysis is the part of cryptology dedicated to the mathematical analysis of the weaknesses of cryptographic algorithms, the goal being to defeat some of the security properties that the algorithm should fulfill, e.g. decrypting data which has been symmetrically encrypted with substantially ...
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If someone breaks encryption, how do they know they're successful?
Let's say I have a file containing a random bunch of bits and then I encrypt it using some modern algorithm (Blowfish, AES, or whatever). If someone captures the file and mounts a brute force attack ...
16
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2answers
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How to estimate the time needed to crack RSA encryption?
How to estimate the time needed to crack RSA encryption? I mean the time needed to crack Rsa encryption with key length of 1024, 2048, 3072, 4096, 5120, 6144, 5120, 7168, 8192, 9216, 10240, 11264, ...
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5answers
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Should RSA public exponent be only in {3, 5, 17, 257 or 65537} due to security considerations?
In my project I'm using the value of public exponent of 4451h. I thought it's safe and ok until I started to use one commercial RSA encryption library. If I use this exponent with this library, it ...
16
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1answer
729 views
WPA significantly less secure than WPA2?
I understand at least theoretically WPA2 is more secure than WPA, but in practice does it make any difference which one you use? From what I know there are no known attacks for either except for ...
12
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3answers
812 views
What's the mathematical model behind the security claims of symmetric ciphers and digest algorithms?
Why can SHA-1 be considered a secure hash function? That's something I still wonder about.
I understand the concepts of why modern asymmetric algorithms are deemed to be secure. They are founded on ...
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3answers
443 views
Are the encryptions “broken” with great computing power?
http://www.dwavesys.com/en/pressreleases.html#lm_2011
Lockheed Martin Corporation (NYSE: LMT) has entered into an agreement to purchase a quantum computing system from D-Wave Systems Inc.
I'm ...
25
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8answers
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How to determine what type of encoding/encryption has been used?
I've looked on this site and on SE. but i couldn't get a handle on this.
Is there a way to find what type of encryption/encoding is being used?
For example, I am testing a web application which ...
15
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3answers
1k views
MySQL OLD_PASSWORD cryptanalysis?
The password hash used for MySQL passwords prior to version 4.1 (now called OLD_PASSWORD()) seems like a very simple ad-hoc hash, without salts or iteration counts. See e.g an implementation in ...
9
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2answers
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Cracking a linear congruential generator
I was recently listening to the security now podcast, and they mentioned in passing that the linear congrunential generator (LCG) is trivial to crack. I use the LCG in a first year stats computing ...
8
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3answers
1k views
time to crack file-encryption password - more than just iteration
I have often seen that takes x amount of time to crack a certain length password. But this just seems to be the amount of time it takes to iterate through all the possibilities. What about the time it ...
5
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4answers
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Brute force vs other methods of recovering passwords from shadow file
Do you know any good approach for de-hashing/actually bruteforcing hashed passwords in the shadow file?
On various operating systems, any good solutions/methods/programs.
Or is it better to upload ...
7
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6answers
557 views
Does repeating one word to form a password result in a similar pattern in its encrypted format?
If i use a single word to form a password by repeating it like the examples below:
securesecuresecuresecuresecuresecure
SeCuReSeCuReSeCuReSeCuReSeCuReSeCuReSeCuRe
...
