The hack works by exploiting the way that full-body scanners project images. When travelers walk through the machines their bodies are projected as white images on a black background. The problem is that suspicious objects are also projected in black. So if the black metallic object is on the side of the white body projected against the black background, it will just blend in. Since there are human eyeballs looking at the screen that's obviously a problem. The blogger, Jonathan Corbett, ran the trial at two different airports and got through both times.
Corbett's trick probably won't work against TSA's new gingerbread man scanners, which project yellow threats against a gray-on-white figure. But it does confirm what we've been insisting for years: simply as matter of what words mean, TSA's full-body scanners weren't ready to get pushed out. The political and public support wasn't there. Security watchers were still highly skeptical. And now it's pretty clear that the people in charge simply didn't think about this long enough.
But hey, at least DC-based scanner lobbieswhich saw their funding double over five yearsdid their jobs.