Educause Security Discussion mailing list archives
Re: Non-administrator advantages / disadvantages
From: Eric Lukens <eric.lukens () UNI EDU>
Date: Mon, 3 Dec 2012 03:14:13 +0000
Since I gave my list of ways to make limited-user rights work better, I’ll also give a list of ways to reduce risk when giving end-users admin rights. 1) Regularly review the list of administrator accounts on the machine, this can be scripted or done via various software programs/administration tools. 2) Have users use a limited account for day-to-day activities and use the admin account as a run-as account to install software. This reduces the likelihood of the user accidentally doing something they didn’t intend to do. 3) Do not let the local admin accounts have access to domain/network-based resources like file shares to reduce the likelihood of using the account for day-to-day activities. Exception, if the software they need to run as an admin is a legacy app that requires admin rights, then some network resources may need to be accessible. 4) Consider a software restriction policy (administered via group policy/sccm or via your Endpoint Protection products). There are lots of ways to use these, but one option is to limit software to the Program Files and Windows folders. For your admin users, you can create a special folder where they can copy program installers that is also permitted (perhaps a special folder on their desktop). This reduces the risk of malware substantially while still giving the users admin rights--and might not be a bad idea for regular users. However, this is an intensive task to get going. Further, some applications that auto-update aren’t going to work well with this method, though you can also allow applications based on the certificates that signed the installers, so you could approve Adobe and Oracle for regular browser plugin updates. Since a software restriction policy can use hash rules, path rules, and certificate rules, it is fairly comprehensive, but admittedly a significant undertaking, but certainly doable. We have departments using software restriction policies with great success. 5) Reputation-based file restrictions. This is another area where Windows 8 makes some improvements, as all Win 8 machines have a reputation-based tool that can be configured to not allow applications that aren’t yet well-known to Microsoft. Such tools also exist in various A/V programs. Policies can be configured to prevent even admin users from launching unknown apps. A sophisticated admin user might be able to bypass the policy to get the software running, but average users are going to be prevented. I’ve encountered some issues with bleeding-edge updates of open-source applications being block by reputation-services, but they usually are corrected within hours of release. 6) Use group policy and other tools to enforce settings that you view as non-negotiable so that admin users can’t change them. Avoid using logon scripts, registry edits, and changes to the default user profile to push settings unless there is no other way to set them (or if the setting has no security implications). Group policy will enforce settings regularly and revert changes made if the user works around a setting. 7) Monitor installed software to make sure your users aren’t installing software they aren’t licensed to use. 8) Consider preventing even the admin end users from launching regedit and perhaps revoke their ability to kill processes. These aren’t fool proof and can cause some compatibility issues with installers that use the user’s privileges to kill processes and merge registry changes with regedit, though such installers are far less common now. Sophisticated users will be able to work around these restrictions. 9) Configure your A/V to not allow end-users to disable it, or require a password to disable it that is only provided if necessary. I’m sure there are more risk mitigations for local admin rights, but these are the ones I came up with off the top of my head that I have used or suggested. -Eric Eric C. Lukens IT Security Policy and Risk Assessment Analyst ITS-Network Services Curris Business Building 15 University of Northern Iowa Cedar Falls, IA 50614-0121 (319) 273-7434 http://www.uni.edu/elukens/ *From:* randy <marchany () vt edu> *Sent:* December 2, 2012 7:21 PM *To:* SECURITY () listserv educause edu *Subject:* Re: [SECURITY] Non-administrator advantages / disadvantages What are we trying to prevent by restricting user from having admin privs? If it's to keep people from downloading evil malware, I hate to tell you this but the primary method of malware delivery is by web drive-bys where a user simply visits a legit www site and the malware is loaded via an infected ad. User downloads are probably a small % of the infection. So here are some questions I believe need to be answered before one implements an arbitrary security solution. 0. IMHO, restricting user privs arbitrarily is a response to an old attack vector. Similar to account lockouts, this was the ONLY defense about 5-10 years ago when there weren't additional controls. Make sure you're addressing the right problem. 1. do you have stats that show the types of infections and their vectors at your site? In other words, do your stats show that users with privs are the primary cause of infection? If so, then it makes sense to restrict user privs. 2. Use your stats to support your security decisions. If your stats show that web drivebys are your primary source of infection then restricting user privs won't make you any more secure. 3. How long does it take for a user to have software that they need for their job installed on their machine? 2-4 hours? 2-4 days? 2-4 weeks? In the SANS classes I've taught, I ask this question and the answers I get back actually range from hours to weeks. I was shocked that it takes more than a day to have software installed on a work machine. I'm not talking about an aquarium screen saver. I'm talking about business software. 4. If you don't have a responsive software install process, your users will bypass your security by simply installing the software they need on their personal machine, copy the data to the machine and do their work. Now, your chances of data exposure increase and you have a worse problem than the one you were trying to solve. So, I believe it's extremely important that you collect the appropriate security stats before making a security decision. Just my .02. -Randy Marchany VA Tech IT Security Office On Fri, Nov 30, 2012 at 4:45 PM, Shalla, Kevin <kshalla () uic edu> wrote: This is a disadvantage from the user’s perspective. They want to do what they want to do when they want to do it. I have to provide support and demonstrate value added. It’s difficult to argue this: “I know you’re the administrator of your own computer at home, and it works for you, and nothing gets in your way, but here at work, we have to slow you down because it’s for your own good, and the good of the university.” We’ve been short of staffing, but still striving towards automating software updates, but so far the only thing we’ve mastered is through group policy, which isn’t very reliable. Further, Adobe and Java are frequently telling users to update, yet when they try, they are thwarted. Thus, we have users questioning our value, and saying “Give me the keys, you guys are too slow”. **** ** ** Kevin**** ** ** *From:* The EDUCAUSE Security Constituent Group Listserv [mailto: SECURITY () LISTSERV EDUCAUSE EDU] *On Behalf Of *Morrow Long *Sent:* Tuesday, November 27, 2012 2:31 PM *To:* SECURITY () LISTSERV EDUCAUSE EDU *Subject:* Re: [SECURITY] Non-administrator advantages / disadvantages**** ** **
Disadvantages****
User cannot install or update some software immediately – have to wait for
desktop support.**** ** ** This is a disadvantage :-?**** ** ** *From:* The EDUCAUSE Security Constituent Group Listserv [ mailto:SECURITY () LISTSERV EDUCAUSE EDU <SECURITY () LISTSERV EDUCAUSE EDU>] *On Behalf Of *Shalla, Kevin *Sent:* Tuesday, November 27, 2012 3:24 PM *To:* SECURITY () LISTSERV EDUCAUSE EDU *Subject:* [SECURITY] Non-administrator advantages / disadvantages**** ** ** I’m trying to highlight the advantages and disadvantages of prohibiting administrator access for users of Windows computers. Can you provide feedback on what I have below? By the way, what’s an example of software that is generally prohibited? Is BitTorrent an example? Is it common?**** ** ** Advantages**** Most malware stays on one user profile, so other users on same machine are unaffected. Deleting the profile can remove the malware. Prohibited (by policy) software doesn’t get installed. Combinations of software known to be problematic are not installed (like multiple active versions of antivirus).**** ** ** Disadvantages**** User cannot install or update some software immediately – have to wait for desktop support.**** ** ** Kevin Shalla**** ** **
Current thread:
- Re: Non-administrator advantages / disadvantages, (continued)
- Re: Non-administrator advantages / disadvantages Steven Alexander (Dec 03)
- Re: Non-administrator advantages / disadvantages Steven Alexander (Nov 27)
- Re: Non-administrator advantages / disadvantages Shalla, Kevin (Nov 30)
- Re: Non-administrator advantages / disadvantages Christopher R Webber (Nov 30)
- Re: Non-administrator advantages / disadvantages Eric C. Lukens (Nov 30)
- Re: Non-administrator advantages / disadvantages Eric Case (Dec 01)
- Re: Non-administrator advantages / disadvantages Shalla, Kevin (Nov 30)
- Re: Non-administrator advantages / disadvantages Geoffrey Steven Nathan (Dec 01)
- Re: Non-administrator advantages / disadvantages Jeff Kell (Dec 01)
- Re: Non-administrator advantages / disadvantages Chuck Braden (Dec 01)
- Re: Non-administrator advantages / disadvantages Harry Hoffman (Dec 01)
- Re: Non-administrator advantages / disadvantages Eric Lukens (Dec 02)