memory not cleared on reboot (Was: cool feature of dmesg.boot file)

[Bert JW Regeer]

On Feb 22, 2008, at 02:25 , Jeremy Chadwick wrote:

> [...]
>
> Interesting tidbit: We have one production machine which when booted
> into single-user via serial console for a world install, retains all  
> of
> the output from that single-user session even once rebooted and  
> brought
> back into multi-user mode.  This poses a substantial security risk,
> especially during the mergemaster phase (we can discuss why if  
> anyone is
> curious).
>
> -- 
> | Jeremy Chadwick                                    jdc at  
> parodius.com |
> | Parodius Networking                           http://www.parodius.com/ 
>  |
> | UNIX Systems Administrator                      Mountain View, CA,  
> USA |
> | Making life hard for others since 1977.                  PGP:  
> 4BD6C0CB |


This is more scary:

http://www.engadget.com/2008/02/21/cold-boot-disk-encryption-attack-is-shockingly-effective/

Which is the exact effect you are seeing.

Cheerio,
Bert JW Regeer