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Security. An Introduction. Security: The 4R Rule. Risk Assessment Define areas of vulnerability Reproachment (Site Hardening) Take steps to isolate and protect site Recovery Have a recovery plan, well tested and practiced Research Stay on top of issues and concerns. Risk Assessment.
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Security An Introduction
Security: The 4R Rule • Risk Assessment • Define areas of vulnerability • Reproachment (Site Hardening) • Take steps to isolate and protect site • Recovery • Have a recovery plan, well tested and practiced • Research • Stay on top of issues and concerns Security: Introduction
Risk Assessment • What can be stolen? • Equipment? Information? Services? Services to others? • Who can hurt you? • Experienced Hackers? Why are you a target? • What can or cannot be replaced? • Can: Equipment. People. • Cannot: Time, Effort, Money, Resources, Trust. • What can be recovered? • From where? In how long? • What is the on-going loss. Security: Introduction
Outside - In Model Firewall The "Internet" Network O/S ISP Application/API Security: Introduction
Outside-In Comments • At each arrow and block there is a vulnerability. • Snooping: Information being transmitted being intercepted and diverted or copied. • Hacking: Breaking into a network or system to steal or destroy. • Cracking: Secretly gaining access and then snooping or hacking. Covert or time delayed attacks or intrusions. Security: Introduction
Between Client/ISP • Encryption • Less perfect then one might suppose • Isolation of connection • Connection intrusion detection • Connection staggering (multiplexing) • Continuous authentication • Physical site security Security: Introduction
Across the Internet • Private networks • Intrusion Detection • Hard encryption • Multi-routing • Bypass wires in favor of tight beam connections (microwave or laser) Security: Introduction
At the Firewall • Only allow TCP/IP • Filter available ports (i.e. ports 80, 20/21, 25) • Filter IP addresses • Filter by packet content • Encryption and authentication at the firewall • Route tracing Security: Introduction
At the network • Isolation of external connections from main backbones • Gateways should refuse to pass packets in packets (tunneling) • Hard to guess accounts and passwords • Logging • Route Tracing • Encryption and authentication Security: Introduction
In the O/S • Minimum number of services/protocols • Rid O/S of all spurious accounts • Long seriously hard to crack passwords, rotated frequently • No unneeded service accounts • Keep current on revisions and patches • Physical isolation of the hardware Security: Introduction
Application/API • Functional restrictions by users/groups • Avoid "all in one" privileges • Prevent certain APIs from being called from unregistered services • Support for encryption and authentication at this level • Database security/Change log/No delete rule. Security: Introduction
Recovery • Physical • Equipment, Power, Connectivity • Operating Environment • O/S, Drivers, Services, Patches • Data • Content • Operational • Broadcast of availability, trust recovery Security: Introduction
Recovery preparedness • Backup and then test backup on a different machine. • You should be able to restore 100% functionality if you have compatible hardware. • New "clone" should be taken after every patch or update • No matter how big data is, a complete snapshot should be taken periodically. Security: Introduction
Media Madness • Media frays. Replace it every 1/2 - 3/4 of Manufactures recommendation. • Clean media drives as frequently as manufacturer suggests. • See previous slide about testing backups via recovery. • Off-site a batch of media periodically. • Protect media from environmental factors (humidity, dust, temperature extremes) and particularly magnetism! • Critical data should be written to non-magnetic media as well. • Document recovery process carefully, practice it! Security: Introduction
Research protocols • For every step in the diagram watch the sites that supply the software/hardware for patches and updates. • Invoke an outside testing agency to assess your site hardness (SATAN and its ilk). • Log and document all patches and carefully ready distributions with patches. • Audit your security periodically. Security: Introduction
NT Security • Domains -- a collection of computers that mutually agree to share the same trust level. • Groups -- a collection of users within a domain with the same access privileges to network resources. • Resources -- all resources are based on access to a file or folder (e.g., a share). For instance, a printer spooler file, a web page, or a shared folder. Security: Introduction
Research Sites • http://www.microsoft.com/security/default.asp • http://www.sans.org/ • http://www.verisign.com • http://ciac.llnl.gov/ciac/CIACHome.html • http://www.symantec.com/avcenter/index.html • http://www.nai.com/ • http://web.mit.edu/network/pgp.html • http://csrc.ncsl.nist.gov/ • http://www.cert.org/ Security: Introduction
Users and Groups • Good practice is to right groups to resources and put users in groups rather than granting individual users rights to resources. • Most meaningful security on NT machines enabled only on NTFS partitions. • If greater than group access is required, NT supports access control lists for files and folders (all resources in Windows 2000) Security: Introduction
Special NT Groups • Administrators: aka God. • Domain Admins: God of this universe. • Machine Administrator: god of this machine. Required to admin services. • Domain Users: people who are users of this domain. • Everyone: a domain user or not. Security: Introduction
User Manager for Domains Security: Introduction
Editing a User Security: Introduction
NT Access Rights • Access rights implemented by Access Control Lists (ACLs) on each resource on an NTFS partition. Security: Introduction
Permissions • Read (open or copy) • Write (create, edit) • Execute (run or run script) • Delete (delete) • Can also implement advanced rights via ACLs • Access by time of day • Access by location • Access by password Security: Introduction
NT Security and IIS • In order to administrate IIS you must have operator or administrator privileges. • All users authenticate to some user, IIS creates the anonymous user IUSR_machinename account to allow anyone to access machine resources like web pages. Security: Introduction
IIS Security Screens Security: Introduction
Blocking Bad Visitors From the LOG files you can determine the IP addresses of bad guests and exclude them. Security: Introduction
FrontPage Security • Sits on top of NT security • Rights to root web and child webs assigned by groups (preferred) or users. • FrontPage security manager does “bulk” changes of ACLs. It spins through the files and subfolders propagating the rights changes indicated. • Front page hides many of the details of the ACL mechanism by having “abstract” levels of rights. Security: Introduction
FrontPage Rights • FrontPage has three levels of rights that match up to specific ACLs • browse: r (read) • author: rwd (read, write, delete) • administrator: rwxdpo (read, write, execute, delete, change permissions, take ownership) (NT: full control) • Certain files in FrontPage (the _Underbar files and folders) require special ACL combinations. Security: Introduction
FrontPage Security Dialog Security: Introduction