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awarded  Student
Sep
24
awarded  Autobiographer
Apr
29
comment Secure Configuration of Ciphers/MACs/Kex available in SSH
Regarding HMAC/MD5, if you knew what the packet was going to look like (your attack payload was static and not dynamic), you could generate this packet well in advance. It would not need to be generated on the fly. I agree that it'd be difficult, and I think this is just a second layer, but I think it may be reasonably practical to use a precomputed collision in MD5 here. The function is : mac = MAC(key, sequence_number || unencrypted_packet) Thoughts?
Feb
4
comment Are there any working proof-of-concept comparison timing attacks?
Thanks for your input! I reimplemented your solution and just repeated a few of the checks and your perceived time correlations are apparently because of program entrance and exit. Fair warning, I did not disable any comipiler optimizations. I can't put code in here and I dont want to create an answer so I'm linking externally for my example. gist.github.com/alexlauerman/8808811
Feb
4
comment Are there any working proof-of-concept comparison timing attacks?
@Polynomial, What do you mean by "about the same"? My "slow" ones are the same for the first ~100 characters so it should take 101 comparisons to see they aren't equal. My fast ones should return on the second comparison. I am thinking you are not seeing the comparison these correlate with, although I could absolutely be wrong. If string comparison timing attacks are supposed to be bruteforceable character-by-character remotely, across the internet, wouldn't 100 characters timed locally would be sufficient?
Feb
4
asked Are there any working proof-of-concept comparison timing attacks?
Jan
31
comment Best practice for data security on a web application
@Thomas, I'm guessing you have looked into this, but be sure the environment variables you're setting are not publicly accessible. It sounds like they are publicly accessible in linux, but not windows (user environment variables of course). stackoverflow.com/questions/12461484/…
Jan
30
awarded  Yearling
Jan
29
answered Best practice for data security on a web application
Jan
27
awarded  Critic
Dec
20
comment How do I decrypt an Adobe Triple DES ECB-mode encrypted password?
Keep in mind those bit lengths only apply to symmetric encryption (a government may be able to crack a 1024-bit RSA key today). Also, various algorithms have weaknesses, so it's not safe to assume that 80-bits is always going to be safe.
Nov
4
comment Remove RC4 from SSL/TLS ciphers in Chromium
@king_julien My list of ciphers was to disable CBC, not RC4, sorry for not being more clear on that since it goes against this thread. It was posted as a reference since I haven't disabled RC4, but I was pointing out that I don't think user27136's list will work in all scenarios if the are using RC4 ciphers from >TLS1.0, and I wanted to provide more info, but then again you dont have to disable all ciphers, just all the ones that are preferred over what you want it to not use. I only disabled CBC for testing by the way.
Oct
4
revised Should a hostname ever be considered a secret?
added 1 characters in body
Oct
4
answered Should a hostname ever be considered a secret?
Oct
3
answered How to defeat CRIME, BREACH, TIME etc… server side (without sacrificing compression)
Sep
11
comment Remove RC4 from SSL/TLS ciphers in Chromium
You also need to disable the ciphers from RFC4346 if you're using TLS 1.1. Here is the list of ciphers I'm using to disable CBC: --cipher-suite-blacklist=0x000B,0x000C,0x000D,0x0011,0x0012,0x0013,0x002F,0x0030‌​,0x0031,0x0032,0x0033,0x0034,0x0035,0x0036,0x0037,0x0038,0x0039,0x003A
Dec
12
answered Is there something like the OWASP top 10 for BizTalk applications?
Dec
12
awarded  Editor
Dec
12
revised Does anyone know how to “tcpdump” traffic decrypted by Mallory MITM?
Added additional info about getting mallory working
Oct
2
answered Does anyone know how to “tcpdump” traffic decrypted by Mallory MITM?