<p>It is a <a href="http://en.wikipedia.org/wiki/Affirming_a_disjunct" rel="nofollow">fallacy of the alternative disjunct</a> to assume that your private key is in fact private, just because a potential other party has not used it: The two events <em>"somebody has gained access to my private key"</em> and <em>"nobody has used my private key"</em> are not disjunct.</p>

<p>If you are uncertain whether your private key has been compromised, you should move your bitcoins to a securely created new address.</p>

CC BY-SA 3.0
2014-09-04T05:19:49.813Z
I had a Blockchain.info account without 2fa accessed 5 months ago and the password changed. I'm still dealing with malware on that computer (which is offline) but strangely the BTC stays unspent. It's strange to say the least
Wizard Of Ozzie
CC BY-SA 3.0
2014-09-03T12:43:38.433Z
2014-09-03T12:43:38.433Z
Murch
<p>Some months ago, using bitaddress.org (offline but using my normal operating system), I made a key pair, copied the key and address to paper and stored a small quantity of Bitcoin at the address. Later, of course, the computer was again connected to the Internet, but the money has not been stolen.</p>

<p>Does the fact that probably no malware captured my private key those months ago suggest that the key is safe? Is it credible that malware would capture an address with small amounts of Bitcoin, but not extract it in the hope that later more would be paid into the same address?</p>

CC BY-SA 3.0
2014-09-03T10:11:49.130Z
There is nothing useful to be said about this. Not all malware searches for Bitcoin private keys, your computer may or may not be effected by malware which we do not know, indeed people could wait for a larger sum of money to become available at that address? Why just not use a new one and make sure that you do not have any malware installed?
Jori
CC BY-SA 3.0
2014-09-04T08:18:23.423Z
I haven't mastered yet how to boot my computer with Ubuntu, so until I have done that the question is HOW insecure my existing storage is. With the present stored amount it would be a nuisance rather than a catastrophe if the money were stolen.
Peter
CC BY-SA 3.0
2014-09-04T08:36:14.200Z
Ubuntu does not guarantee some magical safety. You can be fine on Windows too, and you can be hacked on *nix systems.
Jori
CC BY-SA 3.0
2014-09-04T10:38:29.180Z
Well, I thought the idea was that if you booted up your PC from Ubuntu from a disk or USB, i.e. a system which has never been connected to the net, there is no chance of malware recording your keys. Am I wrong?
Peter
CC BY-SA 3.0
2014-09-04T10:47:22.930Z
That seems reasonable. I don't think much can happen if you boot from something like TAILS, but then you have to redownload the whole chain every time you want to interact with your money. I think you'll need the files (at least the chain) on a USB storage device or something to prevent that.
Jori
<theft><malware>
If Bitcoin is not stolen from an address for some months does it suggest that malware did not capture the key?
Peter
# If Bitcoin is not stolen from an address for some months does it suggest that malware did not capture the key?

(Asked by: username_0 on 2014-09-03)

Some months ago, using bitaddress.org (offline but using my normal operating system), I made a key pair, copied the key and address to paper and stored a small quantity of Bitcoin at the address. Later, of course, the computer was again connected to the Internet, but the money has not been stolen.

Does the fact that probably no malware captured my private key those months ago suggest that the key is safe? Is it credible that malware would capture an address with small amounts of Bitcoin, but not extract it in the hope that later more would be paid into the same address?

**Tags:** theft, malware

> **Comments:**
> **username_1**: There is nothing useful to be said about this. Not all malware searches for Bitcoin private keys, your computer may or may not be effected by malware which we do not know, indeed people could wait for a larger sum of money to become available at that address? Why just not use a new one and make sure that you do not have any malware installed?  
> **username_0**: I haven't mastered yet how to boot my computer with Ubuntu, so until I have done that the question is HOW insecure my existing storage is. With the present stored amount it would be a nuisance rather than a catastrophe if the money were stolen.  
> **username_1**: Ubuntu does not guarantee some magical safety. You can be fine on Windows too, and you can be hacked on *nix systems.  
> **username_0**: Well, I thought the idea was that if you booted up your PC from Ubuntu from a disk or USB, i.e. a system which has never been connected to the net, there is no chance of malware recording your keys. Am I wrong?  
> **username_1**: That seems reasonable. I don't think much can happen if you boot from something like TAILS, but then you have to redownload the whole chain every time you want to interact with your money. I think you'll need the files (at least the chain) on a USB storage device or something to prevent that.  

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## 1 answers

### Answer by username_2 on 2014-09-03. Score: 3

It is a [fallacy of the alternative disjunct](http://en.wikipedia.org/wiki/Affirming_a_disjunct) to assume that your private key is in fact private, just because a potential other party has not used it: The two events *"somebody has gained access to my private key"* and *"nobody has used my private key"* are not disjunct.

If you are uncertain whether your private key has been compromised, you should move your bitcoins to a securely created new address.

> **Comments:**
> **username_3**: I had a Blockchain.info account without 2fa accessed 5 months ago and the password changed. I'm still dealing with malware on that computer (which is offline) but strangely the BTC stays unspent. It's strange to say the least  

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