Web Application Vulnerabilities

In the second half of 2007, 58% of all vulnerabilities affected Web applications. This is less than the 61% in the first half of 2007. This drop in the proportion of Web application vulnerabilities is a continuing trend. From an attacker's standpoint, rather than try to compromise numerous smaller sites, it is better to compromise a specific popular site with a single vulnerability, as this increases the chances of compromising a larger number of hosts.

Source: Symantec Internet Security Threat Report, Vol. XIII