Bugtraq mailing list archives
Re: Remove all admin->root authorization prompts from OSX
From: Baptiste Malguy <baptiste.malguy () fr easynet net>
Date: Fri, 26 Jan 2007 09:36:11 +0100
Hello, About sudo in particular. * You can force for a prompt (5mn by default on Mac OSX,) adding a line such as the following in /etc/sudoers (using the visudo command): Defaults timestamp_timeout = 0 * By default users do not authenticate on a per-tty basis. You can enforce it with the following option: Defaults tty_tickets The last is activated by default on GNU/Linux distro Ubuntu. The reading of the sudoers manual page is a very interesting. Regards, -- Baptiste MALGUY - System Engineer EASYNET PGP Fingerprint: 49B0 4F6E 4AA8 B149 B2DF 9267 0F65 6C1C C473 6EC2 www.easynet.com - phone: +33 1 44 54 70 00 - fax: +33 1 44 54 70 01 -- Marvin Simkin wrote:
I respectfully disagree with this proposal and maybe we should discuss it. Being a member of the admin group is NOT 100% equal to being root. Therefore when you switch from admin group to uid=0 you are escalating privileges. A trojan that gets control of an admin's session should not be able to escalate itself to root without a password prompt, which requires a human to decide (rightly or wrongly...) yes I do want to increase the authority of this process. Sure, an admin should be smart enough not to get trojaned, but what if they do anyway? Maybe a cracker could write a trojan that esclates itself using the powers of the admin group, but why make it easier for those who don't know how? The myth that it should be easy for uneducated users to expose their computers to harm is one reason why certain other GUI platforms have so many security problems. host:/tmp1 sysmsimkin$ id uid=505(sysmsimkin) gid=505(sysmsimkin) groups=505(sysmsimkin), 81(appserveradm), 79(appserverusr), 80(admin) host:/tmp1 sysmsimkin$ ls -ld /tmp1 drwxr-xr-x 3 501 admin 102 Jun 28 2006 /tmp1 host:/tmp1 sysmsimkin$ mkdir /tmp1/tmp2 mkdir: /tmp1/tmp2: Permission denied host:/tmp1 sysmsimkin$ /usr/bin/sudo /bin/bash Password: host:/tmp1 root# mkdir /tmp1/tmp2 host:/tmp1 root# ls -ld /tmp1/tmp2 drwxr-xr-x 2 root admin 68 Jan 25 11:20 /tmp1/tmp2 host:/tmp1 root# exit host:/tmp1 sysmsimkin$ rmdir /tmp1/tmp2 rmdir: /tmp1/tmp2: Permission denied host:/tmp1 sysmsimkin$ /usr/bin/sudo /bin/bash host:/tmp1 root# rmdir /tmp1/tmp2 host:/tmp1 root# exit host:/tmp1 sysmsimkin$ More interesting (to me) why wasn't I prompted for a password the second time? (Yes I know it was designed that way, I'm asking was that the right decision.) Presumably there is a window of vulnerability for a few minutes AFTER you have been root during which you could fall victim to a trojan.
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Current thread:
- Remove all admin->root authorization prompts from OSX K F (lists) (Jan 25)
- RE: Remove all admin->root authorization prompts from OSX Marvin Simkin (Jan 25)
- Re: Remove all admin->root authorization prompts from OSX Baptiste Malguy (Jan 26)
- Re: Remove all admin->root authorization prompts from OSX Ben Bucksch (Jan 26)
- Re: Remove all admin->root authorization prompts from OSX John Smith (Jan 26)
- Re: Remove all admin->root authorization prompts from OSX A. Shaw (Jan 25)
- RE: Remove all admin->root authorization prompts from OSX Marvin Simkin (Jan 25)