screen-unlock.txt

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Helith - 0815  
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Author: Rembrandt  
Date: Known since somewhere in &cant_remember  
Affected Software: screen <= 4.0.3  
Type: Local  
Type: Authentication Bypass  
  
Greets go to: Helith and all affiliated People, t3c0, levent, str0ke,  
hdm, The EOF-Crew, rrlf, herm1t, Solar Designer, softxor,  
Packetstorm, FeFe, kscope, Zarathu, f0rg3, Mr. Joern Alles  
  
Disrespect goes to: A Bank [/]  
And others included into this case...  
  
Personal note: I wanna get MY STUFF BACK!  
This is the last "diplomatic" attemp made directly.  
Contact me if you`re interested into a deescalation.  
Nobody is interested into making the things even more complicated  
or? So make your choice. And you better hurry...  
And this is no blackmailing attemp but others may decide for you  
if you don`t do it.  
IMPORTENT: Turn your brain "ON" this time.  
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I didn`t found a Adv. related to this so I decided to write one. :]  
  
screen is vulnerable to a authentication bypass which allows local attackers  
to gain system access in case screen was locked with a Password.  
  
It has been tested on OpenBSD 4.1 + screen 4.0.3 on x86.  
  
How to reproduce:  
  
Lock screen using ctrl+x  
Choose a Password  
Confirm the Password  
  
Screen asks for a Password to unlock the screen.  
Just press ctrl+c.  
2 seconds later the screen is unlocked and you`ve access.  
  
  
Have fun!  
  
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