[rubendev]

With a capable static analyzer that is not true. In many common cases they can deduce the possible ranges of values based on branching checks along the data flow path, and if that range falls within the buffer then it does not report it.

[tptacek]

Be specific. Which analyzer are you talking about and which specific targets are you saying they were successful at?

[canucker2016]

Intrinsa's PREfix static source code analyzer would model the execution of the C/C++ code to determine values which would cause a fault.

IIRC they were using a C/C++ compiler front end from EDG to parse C/C++ code to a form they used for the simulation/analysis.

see https://web.eecs.umich.edu/~weimerw/2006-655/reading/bush-pr... for more info.

Microsoft bought Intrinsa several years ago.

[tptacek]

I'm sure this is very interesting work, but can you tell me what targets they've been successful surfacing exploitable vulnerabilities on, and what the experience of generating that success looked like? I'm aware of the large literature on static analysis; I've spent most of my career in vulnerability research.

[canucker2016]

PREfix wasn't designed specifically for finding exploitable bugs - it was aimed somewhere in between Purify (runtime bug detection) and being a better lint.

One of the articles/papers I recall was that the big problem for PREfix when simulating the behaviour of code was the explosion in complexity if a given function had multiple paths through it (e.g. multiple if's/switch statements). PREfix had strategies to reduce the time spent in these highly complex functions.

Here's a 2004 link that discusses the limitations of PREfix's simulated analysis - https://www.microsoft.com/en-us/research/wp-content/uploads/...

The above article also talks about Microsoft's newer (for 2004) static analysis tools.

There's a Netscape engineer endorsement in a CNet article when they first released PREfix. see https://www.cnet.com/tech/tech-industry/component-bugs-stamp...