Download
1 / 19
190 likes | 261 Views
Windows NT Security Michael Lucas COSC-573. Windows NT Backgound. Windows NT is a relatively new Operating System, initially released in the fall of 1992. Two versions are available: Workstation and Server. Workstation is for the desktop and Server is for the network.
E N D
Windows NT Backgound • Windows NT is a relatively new Operating System, initially released in the fall of 1992. Two versions are available: Workstation and Server. Workstation is for the desktop and Server is for the network. • Windows NT has gone through many updates, the latest version, 4.0, was released in 1996. • Windows NT, under the ownership of a single company, Microsoft, does not suffer the same level of security issues as operation systems such as UNIX • Although Windows NT has better security than most operating systems, Windows NT has very little security when taken right out of the box. It is important for the administrator to understand and modify all security options appropriate for his or her network.
Security Analysis • Risk Assesment • Vulnerability • Implementation • Auditing
Risk Assesment • Risk assessment is the process of finding out what data you have and how important is it to you. In addition to the importance of the data is the amount of damage you will incur if it is lost or compromised. • Another part of risk assessment deals with who within your organization will have access to the network. In most businesses or organizations there are employees, staff, management and officers. Some can be trusted to access all of the network and others do not have the trust level to access any of the network. The administrator must decide who has access and how much access they may have. • Risk assessment also covers hardware and software analysis. Why spend $100,000 or more on your hardware when $10,000 or less will do. If you stand to lose a lot if your hardware fails then by all means you should invest in the best possible protection.
Vulnerability • Looking around is the first step in assessing the vulnerability of a network • A cubicle with a logged on computer is a potential security risk, anyone who can get to that computer has instant access to the network • If your clients and servers are in a an area that is sensitive enough to be secured with locks, then the administrator must be sure that none of the doors are left propped open or unlocked even for a few minutes. • Check the yellow stickies that are stuck to monitors in offices and under keyboards and desktops. These are favorite places for people to stick their passwords.
Implementation • Common Implementation Steps: • Implementation involves putting your security plan into effect. • Install all service packs, and monitor bug and security updates. • Require strong passwords (combinations of numbers and letters) and require the passwords to be changed at most every 90 days. • Limit physical access to the server, anyone with physical access to the server can gain access to all passwords on the network. • Convert all partitions to NTFS, NT file security only works on NTFS partitions, not the FAT partitions of Windows 95 or 98 • Hide the administrator account by renaming it to something ordinary. Create a decoy account and name it administrator to trap any person trying to gain access to the network. • Audit logon attempts, set Windows NT to disable access after a number of unsuccessful logon attempts. • In larger or sensitive networks use firewalls internally to segment high security areas
Implementation • Auditing is essential for detecting and recovering from an intrusion. Further it helps determine who is causing problems in a network. Audit logs should be reviewed regularly to ferret out suspicious activity. • Segment Network, by breaking the network up into high and low security segments you can focus your security resources on those who need it and provide additional hurdles for hackers to traverse.
Common Network Attacks • Denial of Service • Trojan Horse • Ping of Death • Network Sniffing
Denial of Service • Denial of Service attacks are aimed at devices and networks with exposure to the Internet. Their goal is to cripple a device or network so that external users no longer have access to your network resources. Without hacking password files or stealing sensitive data, a denial of service hacker uses a program that will generate enough traffic to your site that it denies service to the site's legitimate users.
Trojan Horse • Trojan horse attacks are one of the most common and serious threats to computer security • A Trojan horse is defined as a "malicious, security-breaking program that is disguised as something else" such as a screen saver, or a game. The most famous Trojan horse was the "Love Bug" in May 2000. If this apparent love letter was opened, it would unleash a number of problems, such as sending itself to everybody on your email address, erasing or modifying your files, and downloading another Trojan horse program designed to steal your passwords. Many Trojan horses also allow hackers to take over your computer and "remote control" it, using your computer to perform dwnial of service attacks like those that disrupted web sites of Yahoo and Amazon.
Ping of death • Ping of Death exploits a bug in TCP/IP. The Ping of Death uses a ping utility to create an IP packet that exceeds the maximum 65,536 bytes of data allowed by the IP specification. The oversize packet is then sent to an unsuspecting system. Systems may crash, hang, or reboot when they receive such a Ping of Death packet
Network Sniffing • A Network Sniffer is a device that makes it is possible to read data, such as e-mail and passwords as they travel across the network. Most of the information moving within networks is not encrypted and can be read by anyone with a sniffer. Even many passwords are sent in the clear.
Recent Hacking Events • ESPN.com and NBA.com Hacked • 2,397 Credit Card Numbers Stolen, hackers send e-mails to victims. • Yahoo.com attacked and a fake virus scare is distributed • CIA renamed “Central Unintelligence Agency”. • Department of Justice attacked by Swedish Hacking Association. • Department of Defense attacked 250,000 a year, 160,000 attempts are successful.
Do you know your NT password policy is secure? • L0phtCrack 2.5 is the most popular NT password discovery program, it is downloadable from http://www.lopht.com • On a typical Windows NT network, L0phtCrack 2.5 cracked 90% of the passwords in under 48 hours on a Pentium II/300. • 18% of the passwords were cracked in under 10 minutes. • The Administrator and most of the Domain Administrator passwords were cracked. • This network had a policy requiring passwords longer than 8 characters with at least one upper case character plus a numeric or symbol character.
What to do if your network is Hacked • Report it to the Computer Emergency Response Team (CERT). CERT is the central security databaseon the Internet. It accepts reports of intrusions, investigates them, and publishes advisories at regular intervals that recommend security countermeasures. During 1995, CERT documented more than 2,400 computer-security incidents, including over 700 confirmed break-ins.
Security Resources • Computer Emergency Response Team http://www.cert.org/ • Forum of Incident Response and Security Teams http://www.first.org/ • The NT BugTraq Mailing List http://www.ntbugtraq.com/
Hacking Resources • The L0pht Http://www.l0pht.com/ • PWDump Also available at Http://www.l0pht.com/ • Network Associates, Inc., CyberCop Scanner, a network sniffer, is available at Http://www.nai.com
Conclusion • Windows NT can be secure • By default it isn’t secure • Over time users have a tendency yo make it less secure • Always be sure to implement security alerts
