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Date: Fri, 22 Apr 2005 00:14:21 -0500 (CDT)
From: Mike Silbersack <silby@silby.com>
To: Jesper Wallin <jesper@hackunite.net>
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cc: freebsd-security@freebsd.org
Subject: Re: Information disclosure?
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On Fri, 22 Apr 2005, Jesper Wallin wrote:

> Hello,
>
> For some reason, I thought little about the "clear" command today.. Let's say 
> a privileged user (root) logs on, edit a sensitive file (e.g, a file 
> containing a password, running vipw, etc) .. then runs clear and logout. Then 
> anyone can press the scroll-lock command, scroll back up and read the 
> sensitive information.. Isn't "clear" ment to clear the backbuffer instead of 
> printing a full screen of returns? If it does, I'm not sure how that would 
> effect a user running "clear" on a pty (telnet, sshd, screen, etc) ..
>
>
> Best regards,
> Jesper Wallin

I've often wondered the same thing when connected in via a ssh session. 
If there was a way to implement this functionality without uglifying the 
code too much, I don't see why anyone would object to it.

But I don't think you're going to get someone else to code it for you. :)

Mike "Silby" Silbersack