Threats to computers Andrew Cormack UKERNA
Daily reported attacks Code Red (>850) Nimda (1936) As detected by just one MAN (c 5 class Bs) And many of these attacks are thousands of machines
Door rattling? These numbers are from just one MAN And many probes scan thousands of hosts Millions of JANET hosts attacked every day Automated scan/compromise programs If you’re vulnerable you will be compromised Security by obscurity is no longer tenable I think the handle fell off a while ago!
What are the targets? Random Resources Reputation Revenge Retaliation Scripts pick random IP address ranges Resources Intruders like our bandwidth, disk space, CPU power Reputation Intruders gain kudos for compromising high-profile sites Revenge Has your institution upset anyone recently? Retaliation Has one of your (ab)users upset anyone?
What can attackers do? Read, delete, modify your data Misuse your resources So they aren’t available for your users Attack others Leaving you to take the blame Attack you
Real examples All from JANET sites Mostly from automated, dumb, programs Because they can be examined Because they (usually) only do one thing How much more are intelligent people doing?
Threats: access to information Reading private information Viruses actively seek out passwords and credit cards Deleting vital information Department lost all files for six months Vandalism, or just removing traces? Modifying information Are there vulnerabilities in finance, exams, MLEs… ?
Threats: abuse of resources Software piracy Departmental FTP server used for distribution Pornography University systems used to store personal collection Site proxy used by group to access illegal material
Threats: attacking others Compromising systems Worms attempt break-ins to anything running HTTP Denial of Service (DoS) Compromised machines join flooding networks Viruses now carry these tools Real-world crimes Stolen credit card numbers used for purchases Blackmail, defamation, incitement, stalking, …
Threats: attacking you DoS attacks take sites off network Attacker with control of system is “inside” Attack other systems Read traffic on networks Disrupt service Firewall protection failed Social engineering attacks
Some good news Attacking is not rocket science Nor is defending Most successful attacks are preventable Well-publicised vulnerabilities Software fixes freely available Simple toolkit Network configuration Patches
What can you do? Crime prevention Reduce open windows Fit locks Limit direct access from the Internet Fit locks Secure hosts that are exposed or critical Guidelines and tools exist Use them and make sure others do