Why does settting minimum-vt= <7 in lightdm.conf cause security issues?

I much prefer the old way where the graphical environment starts in tty1 and ttys2-7 are open. Now I have tty1 being the last boot output before Cinnamon starts and ttys2-6 are free and tty7 is Cinnamon. Here is the line I am talking about :#minimum-vt=7 # Setting this to a value < 7 implies security issues, see FS#46799. Why are there “security issues”? What are they?


The link says

We are setting the minimum-vt to “1” by default. This should be changed temporarily, if not permanently. Since changing the value in the package will not resolve the issue for users who already have it installed, an advisory should be presented to the user.

which conflicts with the same article that minimum vt should not be below than 7. And minimum vt was set to 7 by default on my system. So the reason I shouldn’t change that is because I don’t want to leak my password and have a thief steal my stuff.

The reporter is stating that at one point the minimum was being set to 1. The follow-up quotes indicate that had already been changed to 7 in more recent configs. Since it is from over 5 years ago, I think it is safe to believe it is no longer set to 1 by default.

The linked bug report is still open so I would recommend assuming that it is still an issue and setting the value to less than 7 creates a security issue where your password can be captured in plain text in the logs under certain circumstances.

Oh. Thanks for clarifying.

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