The PureFunds ISE Cyber Security ETF (NYSEArca: HACK) has been receiving plenty of attention this week and Friday is likely to be an extension of that theme after it was reported that the Federal Bureau of Investigation is looking into a massive data breach affecting federal workers.

The Office of Personnel Management, which stores personal data of government employees was reportedly victimized. News of the hack was reported after the close of U.S. markets Thursday.

“U.S. officials suspect hackers based in China are behind the attack, though they continue to investigate, these people said. One official described it as one of the largest thefts of government data ever seen,” according to the Wall Street Journal.

HACK, the lone cyber security ETF, was not active in Thursday’s after-hours session, ETFs rarely move in notable fashion in after-hours trading, but some of the fund’s holdings were. For example, FireEye (NasdaqGS: FEYE) and Palo Alto Networks (NasdaqGS: PANW) were up 1.7% and 0.74% around 6 PM Eastern time Thursday. Those are HACK’s second- and fifth-largest holdings, respectively, combining for 10.5% of the ETF’s weight as of June 3, according to issuer data.

HACK’s denizens of fans know that in the ETF’s short lifespan (the fund debuted in November), what is bad news in the world of cyber security often proves to be good news for HACK’s price action. The ETF has proven as much on multiple occasions and has done as recently as Wednesday after data out of the U.K. showed cost of dealing with online data breaches there has more than doubled over the past year. [New Highs for Cyber Security ETF]