Re:EUD Security Guidance: Ubuntu 18.04 LTS
by angry_octet on Tuesday July 31, 2018 @12:41PM
(#17654658)
My point is they are crippling the functionality of the computer to achieve a marginal security improvement. The insecurity largely resides on the applications, which it barely touched on. Snaps are great, but anything that can touch X is a problem. Profiles for AppArmor are tricky to get right. If they want to do confinement then dockerised apps is much more effective than treating the end user as the primary threat to guard against. All the effort to prevent end users running binaries won't stop ROP gadgets or prevent kernel breaks. Adding 2FA for login, decent firewall and container networking rules, and syslog reporting, would be far more useful than their bizarre paranoia about users running scripts.
The complaint about LUKS is also bizarre, because the work function for trying one passphrase is enormous by default, and easily configured to be stupendously costly (e.g 30s). Its also quite feasible to boot from a USB key, which has a passphrase wrapped key; when separated from the computer this is very secure. TPM isn't foolproof either, so it comes across as rather ill informed.
Buffer overflows - the guide mentioned both sandboxing (snap/apparmor) and remote low level data collection (auditd). If you don't trust the app, that's about as much as you can do.
Phishing - There's not much the OS can do. 2fa is required on the service itself, but that's not in scope for this doc.
XSS - Since you're connecting through a proxy in the recommended networking setup, there's a chance some known endpoints will be blocked. Again, that's in scope for the remote service, not really the OS setup.
I think they did a good job of describing what can you do as far as end-user workstations go. You could do some improvements by getting a grsec kernel, but that's not really Ubuntu 18.04 anymore. (I wish they mentioned it as an option though)