<html dir="ltr"><head></head><body style="text-align:left; direction:ltr;"><div>I've seen screen flashes of text but it's always been random library code stuff and gdm errors. I've not used lightdm before. Bluntly, the system should never be storing passwords in plain text using any method. It's supposed to be flushed out or overwritten immediately when the user entry is converted to salted:sha256 format. But this is more of why X is notoriously insecure. </div><div><br></div><div>It could also be a random thing that a user "saw" their password in that half second and really perceived it as their password when it was really just crap. Humans make patterns out of everything.</div><div><br></div><div>If someone has a camera with slow motion ability, have multiple people log in then lock the screen and video the "sign in as another user" process in slow motion. If the others see their password in the video, notify Ubuntu and lightdm developers.</div><div><br></div><div>On Tue, 2018-12-11 at 15:02 -0600, Todor Fassl via Ale wrote:</div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><pre>What do you all make of this report from an end user? The user is a grad </pre><pre>student who shares an office with several other students. Right now, </pre><pre>there are 5 of them logged in, they've all failed to log out when they </pre><pre>walked away from the machine.</pre><pre><br></pre><pre> > I was about to use the machine in my [shared] office just now, and had</pre><pre> > to click "sign in as another user". In between that and the list of</pre><pre> > usernames appearing, a black screen with white text on it popped up</pre><pre> > for half a second tops. I noticed it showed my password in plain text,</pre><pre> > and presumably some of the other text was other people's passwords.</pre><pre><br></pre><pre>The system is a fully updated ubuntu bionic system using lightdm for the </pre><pre>display manager.</pre><pre><br></pre></blockquote><div><span><pre><pre>-- <br></pre>James P. Kinney III
Every time you stop a school, you will have to build a jail. What you
gain at one end you lose at the other. It's like feeding a dog on his
own tail. It won't fatten the dog.
- Speech 11/23/1900 Mark Twain
http://heretothereideas.blogspot.com/
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