PSA: LinkedIn single-sign-on dangers
I have a work-issued computer that I keep rigorously separate from my personal stuff. It belongs to my employer and thus I do not keep personal files on it, or access personal email and certainly don’t save personal passwords on it. I even have it on a separate VLAN on my home network.
This is why I was horrified when I went to the LinkedIn website on my work computer (to look at a colleague’s posting) and it automatically started a single sign-on with my company’s GMail (my work address is of course linked to my LinkedIn profile).
This means a company with Google Apps can potentially access your LinkedIn account without your permission. Considering LinkedIn’s past record of egregious security failures1, it shouldn’t be too surprising, but still…
I couldn’t find any setting to disable SSO, and it seems the only way to prevent this is to turn on two-factor authentication (where the only options are the grossly insecure phone SMS text message method or the equally phishable TOTP Authenticator app codes, not the actually secure Webauthn/FIDO U2F USB keys).