Still recovering from a week in Vegas. I have a new founded respect for teachers/professors. The two day intermediate malware analysis course I gave put my voice out of commission. I don't know how it's possible to maintain that for months on end. Talking over loud music definetely didn't help the situation. Vegas was a blast. Caught some good talks at Blackhat, put a lot of faces to names at the various parties- the most amazing of which was the 3Com/TippingPoint party held on Wednesday night at the Hard Rock. There must have been almost a thousand people there and the place was out of control. Who would have guessed that the dance floor of a security conference party would ever fill up. In my (currently unbiased) opinion this party was the best of the week.
I released Process Stalker publicly today, open source and available for download from http://labs.idefense.com. Process Stalking is a term coined to describe the combined process of run-time profiling, state mapping and tracing. Consisting of a series of tools and scripts the goal of a successful stalk is to provide the reverse engineer with an intuitive visual interface to filtered, meaningful, run-time block-level trace data.
Spent some time with spoonm over the weekend at RECON tinkering with the MS05-025 PNG vulnerability. Using my own not-as-cool-as-halvar's bindiff tool I came across the following significant change:
The left column is pre-patch and the right column is post-patch. Further tracing reveals the actual vulnerable loop that leads to heap corruption, a jump table for which case 0x9 is required to reach the vulnerable function and some other interesting tidbits. All in all the vulnerability wasn't difficult to pin point, the biggest hurdle is overcoming the lazyness required to generate a valid PNG image as the CRC checks are done prior to reaching the vulnerable code.