Though the current bug has been patched, Oberheide says Webbugs like the one he found are too common for Google to allow installation of phone apps from the Web without warning.
Unlike other challenges released by Overthewire, Natas focuses exclusively on exploiting web security bugs in servers, according to its creator, Steven Van Acker, a computer science graduate student at Katholieke Universiteit Leuven in Belgium.
Hansen split his dumptruck of Web-browsing bugs into three categories of severity: About half are low-level threats, 10 or so are medium, and two are critical.