The title of “Zero Days,” Alex Gibney’s chillingly astute glimpse into the shadowy world of global cyber warfare, refers to what is known as a zero-day vulnerability — a security gap in a piece of software or hardware that, once exploited for the purposes of an attack, leaves the defender no time to respond. But the term also carries a less technical, more intuitive meaning. The future is now, Gibney’s documentary persuasively argues, and what it holds for all of us is as scary to contemplate as it may be impossible to ward off.
With a crackling sense of urgency only sporadically hindered by its exhaustive reams of data and testimony, “Zero Days” builds to a hypothetical vision of a full-scale world war being fought beyond the reach of public knowledge and accountability. On this invisible new battleground, whole civilizations might collapse without warning, their infrastructures quietly dismantled from within by computer viruses that act in terrifyingly swift, virtually untraceable fashion.
Gibney’s film cuts across subjects and genres with its own fluid, quicksilver intelligence. It is by turns a coolly riveting geopolitical thriller, a potted history of Iran’s nuclear program, an alphabet soup of government acronyms, a detailed primer on exactly how malware operates, and a fascinating experiment in cinematic form that may test the limits of some viewers’ tolerance for lines of impenetrable code flooding a movie screen.
But the film’s chief aim is to provide an in-depth study of Stuxnet, a sophisticated computer worm that is believed to have been devised by intelligence agencies within the U.S. and Israel (though neither country has admitted involvement) in order to attack Iran’s nuclear centrifuges. Given the specificity of Stuxnet’s target, the world might never have known the virus existed had it not accidentally leaked and spread to networks worldwide (it first came to light in Belarus in 2010).
The unwillingness of government officials to speak on the record about the virus becomes an almost comically recurring theme here, and there are times when “Zero Days” plays like a film about the impossibility of making a film about Stuxnet.
But Gibney, whose voice can often be heard in the background, is more frustrated than amused by his chorus of tight lips, and his film mounts its own compelling attack on the culture of secrecy that has allowed the U.S. and other nations to operate without accountability and to invite retaliatory cyberattacks from their enemies.
The conversation flows more freely when the camera settles on New York Times reporter David E. Sanger, offering a cogent summary of his articles on Stuxnet and how it was deployed under the Obama administration.
This is corroborated further, and in great detail, by several anonymous National Security Agency sources, whose statements are performed with terrific showmanship by the actress Joanne Tucker, her voice and appearance digitally altered in a nicely paranoid flourish. Their sardonic accounts (Tucker’s tone is basically “Try and keep up”) convey just how skillfully and secretly the NSA was able to operate within one of Iran’s most highly prized and carefully guarded networks.
Gibney also interviews two Symantec cyber detectives, Liam O’Murchu and Eric Chien, who can’t help but radiate a certain awe as they describe Stuxnet, whose astonishing complexity, sophistication and near-total absence of the usual bugs made them realize that it had almost certainly been engineered at the nation-state level. Can a hyper-malignant worm also be a thing of beauty? “Zero Days” is rarely more compelling than when it’s breaking down how an intricate piece of code could travel the globe, scouring any number of systems but not unleashing its payload until it found its target, operating with the stealth and selectiveness of an electronic angel of death.
☆☆☆ 1/2 out of 5
Director: Alex Gibney.
Running time: 1:56.
Rated: PG-13, for some strong language.