The NSA understands how to design phones that are not just cryptographically secure—Signal probably is—but also have other important properties. See, e.g., p 570 of https://cr.yp.to/bib/1988/diffie.pdf: “each phone shows information about the identity and clearance of the other party on its display”. That information is apparently embedded in certificates possessed by each user. (Conferencing is a separate problem but one that can also have such properties.) Signal doesn't do that. Instead, you're supposed to assess the identity of your contacts out of band—somehow!—and trust that. And yes, you can have STU-III users who have no clearance—I heard a story from a very reliable source about someone who had such a phone and certificate, and used it to call my contact. (I actually know both people in this call, and I'm quite willing to believe that the other party had such a certificate—it's quite in keeping with their personality.)
Individuals setting up random groups from their own contact list is beyond reckless—it's incompetent and arguably criminal, as the article points out. (Btw, you're not allowed to bring personal cell phones into a SCIF—you leave your phone in your car or put it in a locker outside the SCIF.)
Steve Bellovin /
npub1rt…nashz
2025-03-24 17:55:36
Author Public Key
npub1rt8xs3e8gkexg2f5cctjckv57hcffuqaad6jz3wj2gj7vdag0fgqwnashzPublished at
2025-03-24 17:55:36Event JSON
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