Is a passworded WINRAR file an effective encryption method? - page 2.

nosfera2

jr. member

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Quote from: JoelKatz on June 29, 2011, 07:09:55 AM

7-Zip uses iterated SHA-256 as its key derivation function. This is weak against hardware brute force attacks. If your password really is 18 randomish characters, you should be fine. If it's one English word with a few digits before or after it, you are theoretically vulnerable to that kind of attack.

Are you sure? The version I have (Ver 9.20) says AES-256. And yes, 18 random chars.

da2ce7

legendary

Activity: 1222

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Live and Let Live

WINRAR is fine... providing you use a secure password...

The password search space for a Uppercas, Lowercase, Digit, and Symbols 12 digit password is 5.46 x 10^23

That would take over 100 years at one hundred trillion guesses per second. (10x the power of the entire bitcoin network).

useful link: https://www.grc.com/%5Chaystack.htm

JoelKatz

legendary

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Democracy is vulnerable to a 51% attack.

Quote from: nosfera2 on June 29, 2011, 06:56:40 AM

7-Zip has 256 bit AES. I'm using that with an 18 char password and storing my wallet completely and permanently offline, so I'm sleeping pretty well at night Wink

Now I just have to fill it with a few BTC haha!

7-Zip uses iterated SHA-256 as its key derivation function. This is weak against hardware brute force attacks. If your password really is 18 randomish characters, you should be fine. If it's one English word with a few digits before or after it, you are theoretically vulnerable to that kind of attack.

On the bright side, you don't really have to worry about someone stealing your wallet today and then breaking it in ten years when the computing power is available to do so. Shortly before the time any encryption scheme you ever used to protect your wallet becomes vulnerable to an attack (due to increasing computing power, a newly-discovered flaw, or whatever), you can simply transfer all your BitCoins to a brand new wallet using an encryption scheme that is stronger.

nosfera2

jr. member

Activity: 42

Merit: 1

7-Zip has 256 bit AES. I'm using that with an 18 char password and storing my wallet completely and permanently offline, so I'm sleeping pretty well at night Wink

Now I just have to fill it with a few BTC haha!

JoelKatz

legendary

Activity: 1596

Merit: 1012

Democracy is vulnerable to a 51% attack.

Quote from: Fuzzy on June 29, 2011, 05:52:18 AM

This friend I know Roll Eyes

is using winrar to encrypt his wallets with fairly long passwords.
How secure is winrars password encryption, and what's the next most convenient and more reliable form of file encryption?

How long is fairly long? The weak link would be a brute-force attack, and the plausibility of that will directly depend on how many passwords someone would have to try to get to his. There already exists hardware used by law enforcement to brute force WinRAR passwords.
http://www.forensic-computers.com/TACC1441.php

SomeoneWeird

hero member

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Quote from: XIU on June 29, 2011, 06:41:12 AM

Quote from: BitcoinPorn on June 29, 2011, 06:31:28 AM

Go with TrueCrypt.

I know this shouldn't matter, but I think it would be weird to protect something so valuable with a program everyone has on their desktop. I am not sure why I feel like it matters to me, but it does, I can't find the logic in it yet.

Only annoying part is that you have to create a volume that is big enough, because re-sizing isn't really possible (I've saw somewhere about someone having a 150MB+ wallet.dat file)

Just create a 1gb volume and have the entire bitcoin datadir in that.

XIU

member

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Quote from: BitcoinPorn on June 29, 2011, 06:31:28 AM

Go with TrueCrypt.

I know this shouldn't matter, but I think it would be weird to protect something so valuable with a program everyone has on their desktop. I am not sure why I feel like it matters to me, but it does, I can't find the logic in it yet.

Only annoying part is that you have to create a volume that is big enough, because re-sizing isn't really possible (I've saw somewhere about someone having a 150MB+ wallet.dat file)

Fuzzy

hero member

Activity: 560

Merit: 500

Quote from: BitcoinPorn on June 29, 2011, 06:31:28 AM

Go with TrueCrypt.

I know this shouldn't matter, but I think it would be weird to protect something so valuable with a program everyone has on their desktop. I am not sure why I feel like it matters to me, but it does, I can't find the logic in it yet.

Well, just in case my grandma wants to brute force it Cheesy

BitcoinPorn

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Go with TrueCrypt.

I know this shouldn't matter, but I think it would be weird to protect something so valuable with a program everyone has on their desktop. I am not sure why I feel like it matters to me, but it does, I can't find the logic in it yet.

XIU

member

Activity: 84

Merit: 10

Quote from: SomeoneWeird on June 29, 2011, 06:02:30 AM

Quote from: Sukrim on June 29, 2011, 05:59:36 AM

Quote from: SomeoneWeird on June 29, 2011, 05:57:02 AM

WinRAR uses an ineffective encryption standard (afaik).

128bit AES... yeah, sure - very ineffective. NOT!

Ok goshh, they didn't use aes last time I used it.

It has changed since v3.0, so together with a strong password, it'll be secure enough for some time

SomeoneWeird

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Quote from: Sukrim on June 29, 2011, 05:59:36 AM

Quote from: SomeoneWeird on June 29, 2011, 05:57:02 AM

WinRAR uses an ineffective encryption standard (afaik).

128bit AES... yeah, sure - very ineffective. NOT!

Ok goshh, they didn't use aes last time I used it.

Sukrim

legendary

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Quote from: SomeoneWeird on June 29, 2011, 05:57:02 AM

WinRAR uses an ineffective encryption standard (afaik).

128bit AES... yeah, sure - very ineffective. NOT!

SomeoneWeird

hero member

Activity: 700

Merit: 500

WinRAR uses an ineffective encryption standard (afaik). Tell him to use truecrypt.

Fuzzy

hero member

Activity: 560

Merit: 500

This friend I know Roll Eyes

is using winrar to encrypt his wallets with fairly long passwords.
How secure is winrars password encryption, and what's the next most convenient and more reliable form of file encryption?

Topic: Is a passworded WINRAR file an effective encryption method? - page 2. (Read 14899 times)