re 5 in Signal, it is no longer the case, even iMessage (and SimpleX) has more secure PQ encryption implementation than Signal, by rotating PQ keys in ratchet steps - something Signal does not do.
See: https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html
and
https://security.apple.com/blog/imessage-pq3/
You may also look at this:
https://x.com/kaepora/status/1810611336675565934
and this:
https://x.com/kaepora/status/1828466690897703359
Re 5 in Matrix - they can attack key exchange, and compromise e2ee. You cannot just ignore this vector.
SimpleX Chat
npub1gs…zfy6l
2024-09-05 19:32:11 UTC
in reply to nevent1q…jc94
Author Public Key
npub1gsunl7x2y8ka4rn72y9zmzh0j8ntw8ln3956dxe4vg2mldpt4svsuzfy6lSeen on
wss://relay.momostr.pinkPublished at
2024-09-05 19:32:11 UTCEvent JSON
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"content": "re 5 in Signal, it is no longer the case, even iMessage (and SimpleX) has more secure PQ encryption implementation than Signal, by rotating PQ keys in ratchet steps - something Signal does not do.\n\nSee: https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html\n\nand\nhttps://security.apple.com/blog/imessage-pq3/\n\nYou may also look at this:\nhttps://x.com/kaepora/status/1810611336675565934\nand this:\nhttps://x.com/kaepora/status/1828466690897703359\n\nRe 5 in Matrix - they can attack key exchange, and compromise e2ee. You cannot just ignore this vector.",
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