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1. Alexandre Oliva (moved to @lxo@gnusocial.jp) (lxo@gnusocial.net)'s status on Thursday, 16-Sep-2021 20:45:01 EDT Alexandre Oliva (moved to @lxo@gnusocial.jp)
   I wonder, how does matrix deal do end-to-end (?) encryption on multiple devices without keeping a copy of the keys?
   1. lnxw48a1 (lnxw48a1@nu.federati.net)'s status on Thursday, 16-Sep-2021 21:17:31 EDT lnxw48a1

      in reply to
      @lxo That seems to be the reason so many new #Matrix users crowd the element-iOS and element-android rooms, asking about "cannot decrypt" messages.
      1. GeniusMusing (geniusmusing@nu.federati.net)'s status on Thursday, 16-Sep-2021 22:23:39 EDT GeniusMusing

         in reply to
         @lxo @lnxw48a1
         While not directly related, starting on page ten is some very interesting multi-keyed encryption/decryption description.
         Still trying to wrap my head around it.
         
         GRC/Twit Security Now show notes, REvil’s Clever Crypto, aka Sodinokibi.
         
         https://www.grc.com/sn/SN-827-Notes.pdf
         1. Alexandre Oliva (moved to @lxo@gnusocial.jp) (lxo@gnusocial.net)'s status on Friday, 17-Sep-2021 01:08:12 EDT Alexandre Oliva (moved to @lxo@gnusocial.jp)

            in reply to
            not at all related, really. the difficulty of multi-device end-to-end encryption is that you have to encrypt stuff so that all authorized devices, present and (presumably) future, can decrypt it. so a key has to somehow be transferred securely from an authorized device to a newly-added device, that it can then use to decrypt the encrypted messages, or the encryption key used for each message. it's a key distribution problem, which does not appear to be an issue for the ransomware described in the document you linked to