What are the common types of attacks and signatures?
There are three types of attacks: Reconnaissance These include ping sweeps, DNS zone transfers, e-mail recons, TCP or UDP port scans, and possibly indexing of public web servers to find cgi holes. Exploits Intruders will take advantage of hidden features or bugs to gain access to the system. Denial-of-service (DoS) attacks Where the intruder attempts to crash a service (or the machine), overload network links, overloaded the CPU, or fill up the disk. The intruder is not trying to gain information, but to simply act as a vandal to prevent you from making use of your machine. The signatures are written based on these types of attacks.
