Here is an article about the traits of vulnerabilities, exploitation (hacking). It is interesting to see how the landscape has changed, in some respects dramatically.

Below are the key findings. I by no means assume any credit for this. I think the article is worth reading and the findings quite revealing.

Key findings

Large-scale breaches dropped dramatically while small attacks increased. The report notes there are several possible reasons for this trend, including the fact that small to medium-sized businesses represent prime attack targets for many hackers, who favor highly automated, repeatable attacks against these more vulnerable targets, possibly because criminals are opting to play it safe in light of recent arrests and prosecutions of high-profile hackers.

Outsiders are responsible for most data breaches. Ninety-two percent of data breaches were caused by external sources. Contrary to the malicious-employee stereotype, insiders were responsible for only 16 percent of attacks. Partner-related attacks continued to decline, and business partners accounted for less than 1 percent of breaches.

Physical attacks are on the rise. After doubling as a percentage of all breaches in 2009, attacks involving physical actions doubled again in 2010, and included manipulating common credit-card devices such as ATMs, gas pumps and point-of-sale terminals. The data indicates that organized crime groups are responsible for most of these card-skimming schemes.

Hacking and malware is the most popular attack method. Malware was a factor in about half of the 2010 caseload and was responsible for almost 80 percent of lost data. The most common kinds of malware found in the caseload were those involving sending data to an external entity, opening backdoors, and keylogger functionalities.

Stolen passwords and credentials are out of control. Ineffective, weak or stolen credentials continue to wreak havoc on enterprise security. Failure to change default credentials remains an issue, particularly in the financial services, retail and hospitality industries.

I would still suggest reading the article to frame the findings.