cctalk digest, Vol 1 #482 - 53 msgs

From: Johnny Billquist <>
Date: Wed Feb 26 12:22:01 2003

On Wed, 26 Feb 2003 Frank Arnold <> wrote:

> schrieb am 25.02.2003:
> >From: <>
> >To: <>
> >Subject: Help with my PDP 11/73
> >Date: Tue, 25 Feb 2003 12:36:31 -0800
> >
> >I have gotten my PDP 11/73 to
> >start up and go through an initialization
> >script for RSX-11Mplus. However, I do not
> >know any uids/passwords, so I cannot
> >login; I can only watch the script go by.
> >I am able, while the script is running, to break
> >into MCR and run commands like PDP and DMP.
> >I am able to dump in octal
> >some of the files like [0,0]001054.DIR;1.
> >Does anyone know where the user names/passwords
> >are stored? My memory says that the maybe
> >they are not encrypted? Is that so?
> The passwords are stored in a file [0,0]RSX11M.sys if I recall it correctley.
> Should be a rather small file, just pip it to the printer to see it, it should
> be an ASCII-file.
> I think that after version 3.2 of rsx11m passwords were encripted, before that,
> in plain text. Copy this file to some other media and delete it from your
> system disk, After a new cold start you should have an open system. with RUN
> $ACNT you can create new user-accounts if you desire.

This should probably be in an FAQ for RSX.

1. The passwords along with all account information is stored in
2. The file is not an ASCII file.
3. Passwords in RSX11M are not encrypted, while passwords in RSX11M+ are.
4. (and this is the important one) to break into an RSX system:

When the system boots, abort the startup script.
(If it asks for the time, press ^Z, if it just runs ahead, press
^C and type ABO AT. (the period is *not* optional)).
Run $ACNT, which is the account managing program.
Change password for a system account (anything with a group number
<= 10)
Reboot, and then log in.

A small explanation:
When the system boots, the console terminal is privileged.
The startup script normally finished by logging out the console.
If you stop it before that, you'll remain logged in at a
privileged terminal.

This can be regarded as a security problem. Normally it wasn't,
since people are not supposed to have access to the console
terminal of a computer. It's locked away inside the computer hall.
If you want to, you can protect yourself against this exploit,
but noone does.


Johnny Billquist || "I'm on a bus
                                  || on a psychedelic trip
email: || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
Received on Wed Feb 26 2003 - 12:22:01 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:35:56 BST