Do exploit kit authors actually write the exploits they include in their offerings? Sophos' researcher Gabor Szappanos says the answer is a resounding "No."

Having spent the last year following the development of the Blackhole exploit kit, he says the last few exploits for zero-days added to it were all works of whitehat researchers who published their own exploit code online. In one particular case, the Blackhole author practically copy-pasted the published code into his exploit kit's code.

"The author of the Blackhole exploit kit seems to be more comfortable as a system integrator and web application developer than anything else, and is far from being a hardcore vulnerability researcher," he comments.

This revelation should not come as a total surprise, as other researchers have noted a similar pattern.

A little over a year ago, iSec Partners researchers analyzed the (at the time) top 15 exploit kits, and discovered that among the exploits they used - 13 in all - three were developed and used by attackers engaged in so-called APTs, and ten were developed by whitehats.

"To be clear: I am not against vulnerability disclosure. Responsible disclosure helps the overall state of security," says Szappanos. "But that does not have to mean that we have to make the life of malware authors - such as those who deploy the Blackhole exploit kit - this easy."

In fact, he argues that if they were forced to buy exploit code from developers, their earnings would soon dry out.

I doubt that this realization is enough to make whitehats change their behavior, but this idea is surely worth a though or two.