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As with every in-browser encryption deployment - what's the threat model here ? > I now sleep much better at night. If the hosting service gets compromised, i

As with every in-browser encryption deployment - what's the threat model here ? > I now sleep much better at night. If the hosting service gets compromised, it doesn’t really matter as none of the content can be decrypted without the key. Which can be easily exfiltrated by the compromiser as they are now in a position to deliver and run arbitrary javascript in your users browser where the keys reside Also, why can't I draw an actual non-flawed circle ?

3pt14159 7y ago
Well it helped one of those password manager companies during cloudbleed. There is a couple of threat models where it does help. Mitigates bitsquatting too.
1f60c 7y ago
> Also, why can't I draw an actual non-flawed circle ? On my laptop (a MacBook Pro) holding down the Shift key accomplishes that. As for the hand-drawn edges, that's just part of the aesthetic :-)
- seemslegit 7y ago
  Yeah was referring to the edges, if you gonna add a "sloppiness" level in the toolbar might as well have proper edges
smolder 7y ago
Let's say someone vacuums up all the packets going over the wire passively and has some way of breaking TLS. Redundant encryption would be a further obstacle to reading the contents. TLS gets MITM'd in some environments, so it's useful there.
- seemslegit 7y ago
  MITM'd == not passive, so can inject malicious js.
  - smolder 7y ago
    Good point, but what's the relative difficulty of recording all your MITM'd TLS traffic org-wide as plaintext versus attacking specific sites with custom JS to exflitrate JS encryption keys? It's additional friction for lazy spying, mostly, and for a situation where TLS traffic is passively snooped and broken by other means than MITM.
SamBam 7y ago
> As with every in-browser encryption deployment - what's the threat model here ? I believe the biggest win is that existing content will not be accessible to a hacker even if they fully compromise the website, unless users re-open them. So, sure, plenty of content may get compromised if the site gets hacked, but some large percentage of old content will not be. > Also, why can't I draw an actual non-flawed circle ? Adding sloppiness when white boarding is a common pattern to indicate roughness. It subtly cues the viewer not to treat it as a completed product, and allows them more freedom to make changes. If you wanted clean lines, there are many web drawing tools for that too.
- seemslegit 7y ago
  > I believe the biggest win is that existing content will not be accessible to a hacker even if they fully compromise the website, unless users re-open them. So, sure, plenty of content may get compromised if the site gets hacked, but some large percentage of old content will not be. The attacker won't need to wait for the users to open a specific drawing - just browse to the website, from there they can grab the keys for all drawings they have assuming that not that many of them exist in the first place and the attacker has the list of key ids from the compromised backend. It does call for a much more noisy and visible attack which is by itself a valuable mitigation.
  - SamBam 7y ago
    Either I'm not understanding you, or you're not understanding the tech. The website does not store any of the keys. They exist as a url fragment that only the user has ever seen. So if I create an image today and encrypt it, only I see the key. If you hack the website tomorrow, you have access to my encrypted content, but not the key. Now that you control the website, you can modify the code so that the key gets sent up every time a user encrypts or decrypts something. But you don't have any access to anything created before you hacked it, if no user decrypts it.
geofft 7y ago
Depends on the attack, really. Some realistic threats: - The hosting service doesn't wipe physical disks they discard. - The hosting service doesn't wipe virtual disks between customers. - Your offsite backup provider gets compromised. - Someone conducts a non- targeted attack, dumps whatever SQL database they see, and leaves before they get noticed. - Someone conducts a targeted attack but gets noticed before they can develop a working patch to compromise the service. - Someone (e.g., a government) pressures your hosting provider for data but doesn't want you to know. Modifying your JS files would risk being noticed.

3pt14159 7y ago

Well it helped one of those password manager companies during cloudbleed. There is a couple of threat models where it does help. Mitigates bitsquatting too.

1f60c 7y ago

> Also, why can't I draw an actual non-flawed circle ? On my laptop (a MacBook Pro) holding down the Shift key accomplishes that. As for the hand-drawn edges, that's just part of the aesthetic :-)

seemslegit 7y ago
Yeah was referring to the edges, if you gonna add a "sloppiness" level in the toolbar might as well have proper edges

smolder 7y ago

Let's say someone vacuums up all the packets going over the wire passively and has some way of breaking TLS. Redundant encryption would be a further obstacle to reading the contents. TLS gets MITM'd in some environments, so it's useful there.

seemslegit 7y ago
MITM'd == not passive, so can inject malicious js.
- smolder 7y ago
  Good point, but what's the relative difficulty of recording all your MITM'd TLS traffic org-wide as plaintext versus attacking specific sites with custom JS to exflitrate JS encryption keys? It's additional friction for lazy spying, mostly, and for a situation where TLS traffic is passively snooped and broken by other means than MITM.

SamBam 7y ago

> As with every in-browser encryption deployment - what's the threat model here ? I believe the biggest win is that existing content will not be accessible to a hacker even if they fully compromise the website, unless users re-open them. So, sure, plenty of content may get compromised if the site gets hacked, but some large percentage of old content will not be. > Also, why can't I draw an actual non-flawed circle ? Adding sloppiness when white boarding is a common pattern to indicate roughness. It subtly cues the viewer not to treat it as a completed product, and allows them more freedom to make changes. If you wanted clean lines, there are many web drawing tools for that too.

seemslegit 7y ago
> I believe the biggest win is that existing content will not be accessible to a hacker even if they fully compromise the website, unless users re-open them. So, sure, plenty of content may get compromised if the site gets hacked, but some large percentage of old content will not be. The attacker won't need to wait for the users to open a specific drawing - just browse to the website, from there they can grab the keys for all drawings they have assuming that not that many of them exist in the first place and the attacker has the list of key ids from the compromised backend. It does call for a much more noisy and visible attack which is by itself a valuable mitigation.
- SamBam 7y ago
  Either I'm not understanding you, or you're not understanding the tech. The website does not store any of the keys. They exist as a url fragment that only the user has ever seen. So if I create an image today and encrypt it, only I see the key. If you hack the website tomorrow, you have access to my encrypted content, but not the key. Now that you control the website, you can modify the code so that the key gets sent up every time a user encrypts or decrypts something. But you don't have any access to anything created before you hacked it, if no user decrypts it.

geofft 7y ago

Depends on the attack, really. Some realistic threats: - The hosting service doesn't wipe physical disks they discard. - The hosting service doesn't wipe virtual disks between customers. - Your offsite backup provider gets compromised. - Someone conducts a non- targeted attack, dumps whatever SQL database they see, and leaves before they get noticed. - Someone conducts a targeted attack but gets noticed before they can develop a working patch to compromise the service. - Someone (e.g., a government) pressures your hosting provider for data but doesn't want you to know. Modifying your JS files would risk being noticed.