Cross-site Request Forgery (XSRF) Attacks
Cross-site request forgeries (XSRF) occur when a malicious user exploits the trust between a website and a user’s browser. By exploiting that trust, malicious users can execute unauthorized commands on a website.
XSRF attacks rely on 2 items:
Access to authentication credentials
Surreptitious execution of a command via a URL
For more information about XSRF attacks, as well as a few examples, you can visit this Wikipedia page.
http://en.wikipedia.org/wiki/XSRF
Denial of Service (DoS) Attacks
Attacker or group of attackers coordinate against an organization’s network or server resources by sending unauthorized packets to the target host (either server, router, or workstation). This forces the resource to become unavailable to legitimate users.
The most reported DoS case in the US occurred in 2000. Several highly-trafficked commercial and government sites were rendered unavailable by a coordinated ping flood attack using several compromised systems with high bandwidth connections acting as zombies, or redirected broadcast nodes.
Source packets are usually forged (as well as rebroadcasted), making investigation as to the true source of the attack difficult.
Advances in ingress filtering (IETF rfc2267) using iptables and Network Intrusion Detection Systems such as snort assist administrators in tracking down and preventing distributed DoS attacks.
