[comp.sys.apollo] Security alert: tar creates archives with 666 perms!

system@aurum.chem.utoronto.ca (System Admin (Mike Peterson)) (03/01/91)

Tar is creating file archives with 666 permissions, ignoring the
umask specified by the user (and the ACL specified for new files). Example:
	tar cvf tar.archive ~/.[a-z]*
The 'tar.archive' file then has permissions:
	-rw-rw-rw-   1 system   staff      187904 Feb 28 16:04 tar.archive
This is a breach of security since any user can then write over the
tar archive. This is new as of SR10.3/SR10.3.p as far as I know, and
we use the BSD environment.
I don't know of a workaround (although I do scan all user directories
every month for files with "write" permissions for group/other - it
would be much too late by then, and I don't scan the system software
area (yet, but I'll be starting now) ). I will post our hourly, daily
and monthly automated system checks one of these days.
-- 
Mike Peterson, System Administrator, U/Toronto Department of Chemistry
E-mail: system@alchemy.chem.utoronto.ca
Tel: (416) 978-7094                  Fax: (416) 978-8775