Posted by Dan Kaminsky on Feb 08
You need admin rights to create junctions. At that point, path
constraints aren't relevant, just psexec and get not only arbitrary
path but arbitrary code.
The fix is to do what everybody with a directory traversal bug has to
do, block out of path relative directories. In this specific case,
prevent the creation of symlinks where the target is out of the SMB
share's range. (Still allow navigation to such symlinks if one exists,...