Silence on the Wire

Revelation: Phenomenon Reproduced

I was close to giving up. I posted my observations to several public mailing lists (most notably VULN-DEV, a popular vulnerability discussion list hosted by Security Focus), seeking further analysis and feedback from other researchers, but this failed to yield any results. And then, only by sheer luck, I caught one of my own test stations generating this exact behavioral pattern while working on a wholly different problem. I happened to have a sniffer running in the background (don’t we all).

Soon, I had a diagnosis: the problem occurred when the workstation was performing a background file transfer or other network-extensive operations when attempting to establish a connection. In almost every OS, the packet to ...