Could be, theoretically, but this would probably be inconveniencing all syncthing users for a negligible fraction of the userbase. On a shared computer where y

Could be, theoretically, but this would probably be inconveniencing all syncthing users for a negligible fraction of the userbase. On a shared computer where you perceive your peers as a threat, adding a password to syncthing web UI is probably a minor entry in a long list of things you have to do to secure your processes and data, and to ensure the kernel and programs you're running are trustable (in practice, you can't verify that with 100% confidence; they can be backdoored, out-of-date with known security flaws, etc etc). Ensuring security in such a malicious (where your co-workers/peers are apparently a nasty bunch) shared environment is so hard that to begin with that I personally wouldn't put any sensitive data there at all.