Yesterday, outlets including the New York Post, Variety, and the UK’s Independent reported that as much as 30 minutes of hardcore pornography were accidentally broadcast on CNN in the Boston area.

It turns out, though, that the massively viral news was either a hoax, or an isolated incident that was wildly misinterpreted. The entire story appears to have originated from a single pseudonymous Twitter user, who posted photos of pornography running under programming information for Anthony Bourdain’s “Parts Unknown.” Outlets picked up the tweets and ran with them.

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In what now looks like a PR misstep, CNN initially told a Fox affiliate that “The RCN cable operator in Boston aired inappropriate content for 30 minutes on CNN last night. CNN has asked for an explanation.” But both CNN and its local broadcast partner quickly announced that they’d received no similar reports from other viewers.

This might not be a hoax per se. Speaking with Buzzfeed, the Twitter user who started the whole thing has insisted that she really did see some sort of programming glitch, sharing some pretty convincing photos as evidence. She speculates that it was a problem that only affected her cable box. If so, it seems it was the news outlets who did little or no reporting that turned the incident into more than it was.

Most of the outlets that initially picked up the story have backpedaled, changing headlines and adding CNN’s denials. One notable outlier is the Post, which at this writing still hasn’t corrected its headline, despite updating its story.

If you’re ready to go truly meta with this, don’t miss this take from Breitbart News. Breitbart has itself been accused of generating misleading content under the leadership of Steve Bannon, now President-Elect Donald Trump’s lead strategy advisor. But according to Breitbart, the porn non-incident confirms CNN’s own “lack of editorial standards” because the network’s initial statement seemed to confirm a problem.

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Regardless, the lightning-fast path from a few tweets to global headlines highlights the powerful forces encouraging the spread of misinformation on the web, even from nominally credible sources. Fortune is proud to uphold high journalistic standards, but the problem here isn’t primarily about sorting good apples from bad. Media revenue models driven by clicks are motivated by speed more than accuracy, period.

So, while questionable recent reports have outlined a Russian propaganda campaign to use fake news against Hillary Clinton during the Presidential election, let’s not forget we’re perfectly capable of duping ourselves, thanks.