MEGApwn - Bookmarklet to recover your secret MEGA master key
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MEGApwn - Bookmarklet to recover your secret MEGA master key
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Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#2So, does this guy win the chunk of cash that Kim Dotcom promised, or what?
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#3I hope they submitted this to the MEGA Vulnerability Rewards Program https://mega.co.nz/#blog_6
My guess is that it already has, and has been ruled a side-channel/social-engineering attack (requiring either a compromised browser or to run arbitrary javascript on the site).
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#4This JS code needs to be run on the MEGA domain, right? That's why it's a bookmarklet. Other sites don't have access to the local storage required to extract the key. It does mean that MEGA can get the key and send it back to the site if MEGA was compromised but ultimately the client code needs to get the key to decrypt the MEGA content.
Some way of pinning or signing JavaScript verified by a third party or browser would be useful here. If it could also note what percentage of users was using a particular JS version you'd be more likely to notice if a targeted malicious JS was being sent.
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#5I hope they submitted this to the MEGA Vulnerability Rewards Program https://mega.co.nz/#blog_6 My guess is that it already has, and has been ruled a side-channel/social-engineering attack (requiring either a compromised browser or to run arbitrary javascript on the site).
Yea, he did. I think the point is more that MEGA can read the key, and your files without permission. This contradicts their claim "Your data is encrypted by you before upload to our system and therefore we do not and cannot access that content"
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#6This JS code needs to be run on the MEGA domain, right? That's why it's a bookmarklet. Other sites don't have access to the local storage required to extract the key. It does mean that MEGA can get the key and send it back to the site if MEGA was compromised but ultimately the client code needs to get the key to decrypt the MEGA content. Some way of pinning or signing JavaScript verified by a third party or browser w…
Isn't the issue more that Mega portray that they CAN'T see what files you're storing (plausible deniability regarding pirated content) while this proves that they actually could see your file contents if they wanted to?
Which in turn really means it's no more secure than, say, DropBox.
At least that's the impression I have regarding why this is somewhat important.
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#7Thought tptacek's link on Javascript crypto, linked to in the article (and sort of a motivator for the experiment), was well worth a read.
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#8This JS code needs to be run on the MEGA domain, right? That's why it's a bookmarklet. Other sites don't have access to the local storage required to extract the key. It does mean that MEGA can get the key and send it back to the site if MEGA was compromised but ultimately the client code needs to get the key to decrypt the MEGA content. Some way of pinning or signing JavaScript verified by a third party or browser w…
Isn't the issue more that Mega portray that they CAN'T see what files you're storing (plausible deniability regarding pirated content) while this proves that they actually could see your file contents if they wanted to? Which in turn really means it's no more secure than, say, DropBox. At least that's the impression I have regarding why this is somewhat important.
This didn't need proving. They send you JavaScript code, which you trust to encrypt your files. Without a built-in, well-audited, static browser mechanism no web service can ever be trusted with confidential data.
If the Feds decide to raid MEGA again they can simply modify their server side script to recognise your IP and serve you bad JavaScript from the MEGA domain, revealing your keys the next time you login. Nobody would be any the wiser.
Personally I'm waiting for JS crypto to take off big time and idiots to start using it from a CDN.
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#9Earlier quoted context omitted.
Isn't the issue more that Mega portray that they CAN'T see what files you're storing (plausible deniability regarding pirated content) while this proves that they actually could see your file contents if they wanted to? Which in turn really means it's no more secure than, say, DropBox. At least that's the impression I have regarding why this is somewhat important.
This didn't need proving. They send you JavaScript code, which you trust to encrypt your files. Without a built-in, well-audited, static browser mechanism no web service can ever be trusted with confidential data . If the Feds decide to raid MEGA again they can simply modify their server side script to recognise your IP and serve you bad JavaScript from the MEGA domain, revealing your keys the next time you login. No…
Sure, but don't you think it's important that they make this clear?
So far they market heavily on the fact that it's secure when this is simply not true.
If you read their security page, they do say you shouldn't use it if you don't trust them. But that's about it for any warning that you're basically sitting there naked.
I know no security system is entirely secure, but they aren't generally targeting security minded folks, they're targeting the layman who reads what they say and then thinks they're secure due to their weasel worded security page.
Re: MEGApwn - Bookmarklet to recover your secret MEGA master key
#10Earlier quoted context omitted.
Isn't the issue more that Mega portray that they CAN'T see what files you're storing (plausible deniability regarding pirated content) while this proves that they actually could see your file contents if they wanted to? Which in turn really means it's no more secure than, say, DropBox. At least that's the impression I have regarding why this is somewhat important.
This didn't need proving. They send you JavaScript code, which you trust to encrypt your files. Without a built-in, well-audited, static browser mechanism no web service can ever be trusted with confidential data . If the Feds decide to raid MEGA again they can simply modify their server side script to recognise your IP and serve you bad JavaScript from the MEGA domain, revealing your keys the next time you login. No…
The article isn't proving anything, it's an example of how a known problem affects MEGA. It's saying encrypt your files first, because trusting MEGA (or anyone who uses that kind of encryption) is not enough.