Originally published in Information Security, May 2008
This was originally published as the first half of a point/counterpoint with Marcus Ranum.
The standard way to take control of someone else's computer is by exploiting a vulnerability in a software program on it. This was true in the 1960s when buffer overflows were first exploited to attack computers. It was true in 1988 when the Morris worm exploited a Unix vulnerability to attack computers on the Internet, and it's still how most modern malware works.
Vulnerabilities are software mistakes—mistakes in specification and design, but mostly mistakes in programming. Any large software package will have thousands of mistakes. These vulnerabilities lie dormant in our software systems, waiting to be discovered. Once discovered, they can be used to attack systems. This is the point of security patching: eliminating known vulnerabilities. But many systems don't get patched, so the Internet is filled with known, exploitable vulnerabilities.
New vulnerabilities are hot commodities. A hacker who discovers one can sell it on the black market, blackmail the vendor with disclosure, or simply publish it without regard to the consequences. Even if he does none of these, the mere fact the vulnerability is known by someone increases the risk to every user of that software. Given that, is it ethical to research new vulnerabilities?
Unequivocally, yes. Despite the risks, vulnerability ...