The complete version of this article by Avast security developer Alfredo Ortega, originally appeared on The Hill.

Hacking into a country’s electronic voting system is something I am familiar with. I can tell you right now that focusing on the security of the devices themselves is not the big issue at hand. The fact is, every digital system can be hacked, and those who tell you otherwise are lying.

This particular hack took place during the 2015 elections in Buenos Aires. I broke into an unusual e-voting system called Vot.ar, which relies on paper ballots with embedded RFID chips. Vot.ar source code was leaked to the internet, and myself and a few colleagues discovered a major flaw in the vote counting logic. As a result of this flaw, an attacker could manipulate the data stored in the RFID chip so that a single ballot would be counted as multiple votes. I informed the Argentinian congress, so they were able to resolve this problem.

In this year’s U.S. presidential election, hackers have taken an active role. U.S. officials and researchers blame Russian hackers for the Democratic National Committee email hacks and the hacking of voting systems in Illinois and Arizona. While Russia and most other powerful countries seem to have very competent and talented state-sponsored hackers, what most don’t realize is that the vulnerable state of America’s voting systems and machines isn’t necessarily the issue.

The numerous ways to tamper with voting systems

Hackers can manipulate voting systems without ever having to touch physical ballots or machines. Stealing personal data could result in identity theft, but I think it is more likely that they are looking for voting history and seeing if there’s an opportunity to influence future votes through bribes or threats.

In Dutch elections, electronic voting machines that weren’t connected to the internet, were remotely accessed by hackers from 20 to 30 meters away by using a small antenna to listen for the machine’s radio emissions. This removed the anonymity of the voter. In the Illinois voting systems case, hackers extracted up to 200,000 voters’ personal information.

Another more insidious plan is that hackers want to blur the lines between winners and losers. Digital systems raise questions of legitimacy and can cause the losing side to be critical of the results. Republican nominee Donald Trump has repeatedly raised the issue of “election-rigging” and refused to say that he would accept its result, already planting the seeds of uncertainty.

Assume election systems have already been hacked

E-voting hacks don’t take place on election day; rather they are usually set up or planted months, sometimes years, in advance. The assumption has to be that come the day of the vote, you’ve already been compromised.

The most secure option Americas have at this point is to avoid the use of digital devices at all. While it may be impossible to move completely away from electronic voting methods, the US could implement systems with a paper ballot backup that can be read for recounts.

Take it from a hacker, the most dangerous thing U.S. election officials and citizens can do is to minimize security issues and then forget about them once election day passes. Hacking an election doesn’t only require hacking a machine – it requires the inaction of those the attacks target.