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After the Lavabit shutdown, Ladar Levison (founder of Lavabit) announced that he’s "looking into setting up a site where users can download their data".

Such a site is now online: https://liberty.lavabit.com/ (currently it only offers to change your password)

The page says:

Due to concerns about the continued integrity of customers’ passwords, we are offering a short window of five days in which users can change their password before we allow anyone to download an archive of their stored emails. The download functionality will be available starting Friday, October 18th at 7pm CT.

Since the SSL certificates formerly used to protect access to Lavabit have been compromised, we recommend manually validating the serial number and fingerprint your computer received before using this website.

Serial: 00:C9:FA:44:62:08:82
Fingerprint: 8C:18:BF:AB:8C:D1:24:A3:76:8C:FC:C0:4A:89:1D:23:3A:25:DF:77

Now I wonder: Can this site be trusted?

  1. What is the reason for allowing password changes only for five days in this context?

  2. Does it make sense to check this Serial and Fingerprint, as they are printed on the same webpage the cert is used on?

  3. Is there a way to make sure that this new site resp. the SSL certificate is not under control of the FBI?

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Can this site be trusted?

No.

Well, not if you consider GoDaddy subverted or subvertable. As even the published serial number or website could be an FBI plant ;-).

But if you want your emails, you'll need to connect to the site.

What is the reason for allowing password changes only for five days in this context?

We are assuming that the government can't coerce Ladar Levison via a gag order to provide the new private key or update his site's listed serial number within the time frame provided.

Does it make sense to check this Serial and Fingerprint, as they are printed on the same webpage the cert is used on?

No, but Ladar is probably discreetly distributing the current serial throughout the internet.

For example, if the cited serial changes compared to the (original revision) post on Stack Exchange then the spooks may be performing a man-in-the-middle. Still, it doesn't protect against Ladar giving up the current private key though (assuming he doesn't take a 5-day vacation in Rocky Mountains without mobile phone contact and the only copy of the server's access credentials).

Is there a way to make sure that this new site resp. the SSL certificate is not under control of the FBI?

No. Of course any centralised email product requires trusting the provider hasn't had the new key beaten out of them - or that the new server layout and email communiqué isn't the Feds in disguise. In practice Ladar should speak the serial number (and show on a paper placard) in a YouTube video while showing his face and other 'biometric' credentials.

  • 3
    This reminds me of an old movie in which the terrorist holds a gun towards the head of the president's daughter behind the camera. – Hendrik Brummermann Oct 16 '13 at 8:48
  • @HendrikBrummermann This one?? – vikki Oct 16 '13 at 12:13
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    Even with the suggested YouTube video, you cannot guarantee that Ladar has not shared the key with the FBI/CIA/NSA/Other TLA Org. – Iszi Oct 16 '13 at 13:06
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    A video could at least prove that the current website was actually set up by Ladar; hence a rough "biometric bootstrap" of the 'identity' part of the trust chain without solely relying on subverted Root CAs. Of course, this doesn't ensure that Ladar isn't now working hand-in-glove with the NSA or HAL 9000, but then even if Steve Ballmer met you in person and handed you the microsoft.com public key on a USB stick - you have no guarantee whether Microsoft is selling secrets to a cartel of evil Power Rangers. This risk is what LavaBit's customers accepted when they chose a centralised service. – LateralFractal Oct 16 '13 at 13:35
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    Well, the good news is that since liberty.lavabit.com is configured such that there are no ciphersuites with forward secrecy enabled, all the Feds have to do is capture the traffic now and then ask for the private key later at their convenience. – Reid Oct 16 '13 at 13:35
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What is the reason for allowing password changes only for five days in this context?

It might speculate on the government being slower to get a court order. But given enough priority, they can be very fast. I know little about USA law, in German the police has additional permissions in case of "imminent danger".

Another reason might be to put pressure on the users to quickly act and provide there passwords. This is a tactic which is often used by lawyers who want to put pressure on average people.

Edit: As jpkrohling and Reid have pointed out, the server is not using Perfect forward secrecy. So if they server key is obtained in the future, recorded traffic can be decrypted. /Edit

Does it make sense to check this Serial and Fingerprint, as they are printed on the same webpage the cert is used on?

It may be a good idea, to write the real fingerprint down, as there may be other ways this information is published in the future. The problem here is, that using this site will tell the server operators the original password immediately.

The information on the website itself is worthless, but it may raise awareness.

Is there a way to make sure that this new site resp. the SSL certificate is not under control of the FBI?

This is not a problem rooted in technology or math, but in the trustworthiness of the operators of the servers. According to press coverage and court documents, the USA put a lot of pressure onto the server operator in the past. There seems to be no obvious reason why this might have changed.

Or to put it very straight:

xkcd: 538 Security

xkcd: 538 Security

But we have to see this in context: Other email providers, especially the large ones, faced the same pressure, and gave in easily. Furthermore, without additional steps, emails are unencrypted and are gathered on their way through the Internet at various locations.

This is a difficult topic: On the one hand, we know e. g. from East Germany that powerful secret governmental organizations are bad. But on the other hand we do want criminals to be caught and assaults to be prevented.

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What is the reason for allowing password changes only for five days in this context?

The only reason I can think of is that the downloaded file would be a ZIP-like file, protected with this new password. I didn't have an account there, so, I can't test this.

Does it make sense to check this Serial and Fingerprint, as they are printed on the same webpage the cert is used on?

As others have mentioned already, no. The fingerprint should have been posted in a secure communication channel, different than the one consuming the information. As it currently is, there's no way of certifying that this information is real, that the information wasn't spoofed and that the information was posted by the entity claiming to have posted (ie: we don't know if it's really Lavabit publishing it, even though Go Daddy says so).

Is there a way to make sure that this new site resp. the SSL certificate is not under control of the FBI?

No. At this time, we should assume that other parties have access to the keys. The only way to ensure that the communication done today cannot be decrypted in the future is to the server owner to configure it to support "Forward Secrecy", which is not the case with this new service. So, it's safe to assume that some entities are storing all the traffic to this service and might request the new keys in the future, allowing them to decrypt the whole traffic.

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