[Info-vax] How dangerous is it to be able to get into DCL supervisor mode ?

[Simon Clubley]

On 2017-07-03, Simon Clubley <clubley at remove_me.eisner.decus.org-Earth.UFP> wrote:
> This weekend, I found a way to crash DCL on VMS Alpha v8.4 which causes
> the process to terminate with a register dump. The PS register confirms
> the process was in supervisor mode when it failed.
>
> I don't know if the crash is controllable let alone if it's exploitable
> and it looks like it's going to be quite a bit of work to be able to
> get further clues.
>
>==> TO REPEAT: at the moment, this is nothing more than a way to be
> able to take down a specific version of DCL running on a specific
> architecture (Alpha).
>

Just to confirm for the people not familiar with the implications of
the above terminology. I am saying I have a way to crash a specific
version of DCL on Alpha. I do not currently have a way to get into
supervisor mode with my own code but additional research may possibly
reveal a way to control the crash in such a way that I might be able
to get my own shellcode running in supervisor mode.

That's what the additional work and the exploitable comment above is
referring to.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world