So, I have an interesting problem. The root password on one of our Sun x4500 machines was changed and never communicated. Now, nobody knows what it is. I have physical access to the machine, but no Solaris installation disc. Is there any way to reset the password, this way?
Any linux/bsd distribution which can mount your drive filesystem should have the same capability.
A FreeBSD liveCD would likely be your best candidate in the absence of the Solaris media. (BSDs support UFS.)
Here is a step-by-step guide to resetting the root password on Solaris 10, it requires you have the Solaris 10 installation disc, and physical access to the machine though.
Use the OpenSolaris Live CD: http://www.opensolaris.com/
Boot the Live CD and mount your partition...then clear out the password in the shadow file.
This will work if you're using UFS or ZFS root.
The one time I've had to do this without physical or console access, I managed to find a privilege escalation exploit that applied to my OS and patchlevel and got a root shell that way. Might be a long-shot, but otherwise I'd take a look at http://www.sysresccd.org/, since it appears to support ufs.