The Russians have just given us an August glimpse of a potential October surprise.

We learned earlier this summer that cyber-hackers widely believed to be tied to the Kremlin have broken into the email of the Democratic National Committee and others. The Post’s Ellen Nakashima reported Monday night that Russian hackers have also been targeting state voter-registration systems. And, in an apparent effort to boost Donald Trump’s presidential candidacy, they’re leaking what they believe to be the most damaging documents at strategic points in the campaign.

Last week, we learned something else: The Russians aren’t just hackers — they’re also hacks. Turns out that before leaking their stolen information, they are in some cases doctoring the documents, making edits that add false information and then passing the documents off as the originals.

Foreign Policy’s Elias Groll reported last week that the hackers goofed: They posted both the original versions of at least three documents and their edited versions. These documents, stolen from George Soros’s Open Society Foundations, were altered by the hackers to create the false impression that Russian anti-corruption activist Alexei Navalny was funded by Soros. A pro-Russian hacking group, CyberBerkut, had inserted Navalny’s name, bogus dollar amounts and fabricated wording.

This raises an intriguing possibility: Are Vladimir Putin’s operatives planning to dump edited DNC documents on the eve of the presidential election?

Republican presidential nominee Donald Trump says it's "far-fetched" and "ridiculous" to say Russia hacked Democratic Party emails to help him become president. (Reuters)

Perhaps they’ll show that the Clinton Foundation has been funding the Islamic State, or they’ll have Hillary Clinton admitting that she didn’t care about those Americans who died in Benghazi after all. Maybe they’ll show that she really did lose most of her brain function in that fall several years ago and is now relying on Anthony Weiner to make all of her decisions.

Russian “dezinformatsiya” campaigns such as this go back to the Cold War; the Soviet portrayal of AIDS as a CIA plot was a classic case. But this type of cyberwar — email hacking and, now, the altering and release of the stolen documents — is a novel escalation. It’s tempting to wonder how differently the Cold War might have gone had there been cyber-hackers back then. We’ll never know, of course, because the Soviet Union crumbled before Al Gore invented the Internet.

But it’s clear that Russia’s disinformation wars are as active as ever. On Sunday, Neil MacFarquhar wrote in the New York Times about Russian attempts to undermine a Swedish military partnership with NATO. The campaign is spreading false information that there’s a secret nuclear weapons stockpile in Sweden and alleging that NATO soldiers could rape Swedish women with impunity. This Russian use of “weaponized information” helped cause confusion in Ukraine in 2014, when conspiracy theories spread by the Russians about the downing of a Malaysia Airlines jet helped Russians justify their invasion of Crimea.

So does this point to a Putin-sponsored October surprise?

Putin has meddled in domestic politics in France, the Netherlands, Britain and elsewhere, helping extreme political parties to destabilize those countries. He appears to be doing much the same now in the United States, where, in addition to the DNC and state voter system hacks, there have also been reports this summer about Russia hiring Internet trolls to pose on Twitter and elsewhere in social media as pro-Trump Americans. Trump and Putin have expressed their mutual admiration, and even after the departure of Trump campaign manager Paul Manafort, Trump and several top advisers have close ties to Moscow.

The hyper-competitive American media environment is vulnerable to the sort of technique the Russian hackers used in the Soros case — stealing documents, altering them, then releasing them as the original. If Putin’s hackers were to release such a doctored document smearing Clinton in, say, late October, it’s likely that competition would lead outlets to report on the hacked documents before they had a chance to see whether and how they were altered.

We don’t know what, if anything, Putin’s hackers have planned for this fall. But the doctored Soros documents could be a clue.

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