Post #4326699
2026-08-02 09:30 UTC
Replies (1)
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@david_chisnall@infosec.exchange 2026-08-02 09:43
@bazkie@beige.party "mobile operating systems include a load of security features" it's a hypercorporate, locked down platform, if that's what you mean.. I wouldn't trust a smartphone ever. corporations wouldn't trust a desktop ever. hmmm No, I mean that desktop operating systems run apps, by default, with ambient authority. Mobile systems run them sandboxed with explicit permissions. There is no real way on most desktops for a user who doesn’t want to write low-level security policies to run an app that has private state that is protected from other apps that they run. Every single app that you run on a desktop (unless you’re manually configuring SELinux policies or similar) has the ability to read every Signal message that you have and all of your credentials, without needing any OS exploits. Pretty much all mobile devices have a hardware credentials store that makes it possible to store keys that cannot be exfiltrated from the device even with an OS-level compromise. Most PCs have a TPM that can kind-of do this, but they’re not particularly reliable or consistently exposed via useful abstractions (and they need this because the key storage is very limited). The pushback Microsoft got from requiring an absolutely minimum viable hardware security module for Windows 11 was enormous because it made a huge number of PCs ewaste overnight and the requirements for Windows 11 were far weaker than most decade-old mobile devices have. Without that, the app cannot protect data at rest, so anyone who can boot the system can access all Signal messages and credentials without needing Signal to be running. Desktop operating systems are not fit for purpose when it comes to security. They evolved from minicomputer operating systems, where the primary security goal was to isolate users from each other. Modern systems need to be able to isolate programs (or security contexts smaller than a program) from each other, following the user’s explicit sharing policies.