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Reset the SYSTEM password on OpenVMS 8.4

Published: 03-02-2021 | Author: Remy van Elst | Text only version of this article


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This short post shows you how to reset the SYSTEM account password on a single OpenVMS 8.4 ALpha machine via the serial console. You need physical access to the machine and the procedure looks a lot like linux and appending init=/bin/bash to the GRUB commandline to boot into single user mode. It is tested on the AXPbox Alpha emulator, I forgot my password after not using it for a month.

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This procedure was tested with the AXPbox Alpha emulator and VSI OpenVMS 8.4-1.

Boot into single user mode

Type following command in boot console to perform a conversational boot:

P00>>> boot dqa0 -flags 0,1

Replace dqa0 by your boot device.

Enter the following commands in the next prompt to boot into single user mode:

SET/STARTUP OPA0:
SET WINDOW_SYSTEM 0
SET WRITESYSPARAMS 0
CONTINUE

Type following DCL commands to reset the SYSTEM account password:

SPAWN
@SYS$SYSTEM:STARTUP
SET DEFAULT SYS$SYSTEM:
RUN SYS$SYSTEM:AUTHORIZE
MODIFY SYSTEM /PASSWORD=example

Exit out of UAF with CTRL+Z and reboot the system (SHUTDOWN or REBOOT) and you should be able to login with the newly reset password.

Linux?

On Debian systems you can reset a root password by rebooting, appending init=/bin/bash to the linux line of GRUB (bootloader), remounting the disk as read-write (mount -o remount,rw) resetting the password (passwd) and rebooting (exec /sbin/init 6). You need physical access as well and the OpenVMS procedure is very similar, albeit with different commands.

Tags: alpha , axpbox , blog , dec , es40 , openvms , security , vax , vms