On 13/03/2021 14:25, Ivan J. wrote:

On Fri, Mar 12, 2021 at 06:52:17AM +0000, jim bell wrote:

...

BleepingComputer: Europol 'unlocks' encrypted Sky ECC chat service to make arres ts. [1]https://www.bleepingcomputer.com/news/security/europol-unlocks-encrypted-sky... ecc-chat-service-to-make-arrests/

Funny, because I've met drug dealers who all had/have burner Blackberries with Sky ECC, and they all their ops went through the messaging app. From what I've seen (and remember) the app seems to have had some kind of message selfdestruct, and an additional unlock decoy password that is supposed to erase the local messages when input.

Plus sometimes a remote message destruct by the service in emergency - which can sometimes be considered to be the crime of illegally obstructing a criminal investigation. A (not-so-brief) history The (in)famous PGP Blackberries were first sold by ghostpgp, TopPGP etc. from about 2000. Blackberry themselves never made a PGP blackberry. Network-limited crypto phone networks (initially exclusively using PGP Blackberries), where only people on the network could be contacted and people are identified by pseudonyms rather than by phone numbers, started in about 2012. By 2016 Ennetcom was the biggest limited network. Afaik no direct cryptanalytic attack against the PGP Blackberries has ever succeeded, though several hardware-, phishing-, software-, security- and law- based attacks have. Around Jan 2016 it became widely known that the Police could examine the contents of at least some PGP Blackberries after they seized them, and over the next 18 months there were many breaks in service and occasionally security in limited networks. As a result both PGP Blackberry limited networks and PGP Blackberries themselves went somewhat out of fashion. The main method the Police used was to break up the limited networks by seizing servers and arresting operators for associated crimes like money laundering or assisting criminals, rather than trying to obtain plaintext evidence against users. Defunct PGP Blackberry network limited companies include: Ennetcom (19k-40k users). Servers with 48 hours of messages seized in April 2016, those and other messages decrypted shortly thereafter - the Ennetcom servers were generating the PGP private keys... Number of users arrested unknown but more than a few, including some convicted of murder. PGP Safe May 2017. 4 people in the company arrested for money laundering. Few if any users arrested. Phantom Secure (20k users). Highly customised PGP Blackberries. Was broken up in 2017 but not message-security-broken. CEO was busted under RICO, refused to add backdoor, got 9 years. No? users were arrested. Both ordinary and network-limited PGP Blackberries are still available. Next in the limited networks (but not PGP Blackberry) game came Encrochat (60k users). They used their own non-PGP crypto software on mostly Android phones, optionally Blackberries. They were widely message-security-broken in 2020. No arrests in the company afaict, which was apparently a bit more respectable than Phantom Secure or Sky Global. About 1,000 users arrested. The method used in this break is interesting, a LE malware attack: the French Police sent a "software update" to all the phones in use, which then sent the plaintext contents of the stored messages in the phones to the Police at intervals. The system servers were not directly affected. Most recently there is SkyECC (70k users) from Sky Global, again using their own software and mostly Android phones with a Blackberry option. Widely message-security-broken according to LE in 2021. Sky Global's CEO is under indictment for RICO. Many users have been arrested. Sky Global claim that an unconnected and unauthorised "reseller" of fake "SkyEcc" phones sold the phones which were message-security-broken, and their system is still secure. Doubtful, but not impossible. One thing (among many) which confuses me about this is that Sky Global claim they knew about the fake phones for several years - so why did they still allow the fake phones connectivity and crypto services? Peter Fairbrother

On Sun, Mar 14, 2021 at 05:04:57PM -0400, David Barrett wrote:

On Sun, Mar 14, 2021 at 3:55 PM Peter Fairbrother <[1]peter@tsto.co.uk> wrote:

Afaik no direct cryptanalytic attack against the PGP Blackberries has ever succeeded, though several hardware-, phishing-, software-, security- and law- based attacks have.

Given that every real world example finds a weaker place to attack than the encryption, is there anything about the Signal app that is more inherently secure than any of these? It would seem that there's no real protection against someone in control of the network deploying a back door onto your device that siphons off the messages after they are decrypted (or the decryption keys themselves), and it seems like that's a way easier way to get the messages than actually bothering to talk with the app developer. Furthermore, unless everyone involved is willing to go to jail, it seems there's no real protection against compelling the software developers to ship a backdoor. Even being open source with verified builds only confirms that a specific update has a specific version -- the next update, or your friend's update, might have a different build. Indeed, being open source makes it easier for an attacker to craft a build with a back door, and then convince Google to deploy it to their target. Ultimately e2e seems like a real way to force lawyers to bring any discovery requests straight to you for civil suits (because no civil suit could realistically convince Google or Verizon to ship a back door to your phone, whether by a custom build or a fake OS update). But it feels like security theater to assume e2e provides really any protection at all against serious criminal suits, and certainly nothing approaching national security. -david

Unfortunately I'm yet to see some "mainstream" messaging app that is both convenient and _very_ secure to use. But perhaps this should be mitigated with other things, like full disk encryption and this sort of stuff, not placing trust in random app developers. Best regards, Ivan