The notorious online forum 4chan was reportedly compromised in a security incident on Tuesday.

As of this writing, 4chan's website was inaccessible, and social media users indicated the site experienced intermittent outages spanning several hours.

Discussions on a competing forum, reviewed by TechCrunch, praised the intrusion, with one participant asserting the perpetrator of the breach had been within 4chan's network "for more than twelve months."

Screenshots that seem to show 4chan's internal system were shared online. These screenshots showed the site's back end, source code, and ways to ban users. Only the site's moderators should be able to see these things. The leaked information also included a list of people who are supposedly 4chan moderators and 'janitors.' Janitors are users who can remove posts and threads but have fewer powers than moderators. Moderators, for example, can see users' IP addresses.

Because 4chan is known for its links to violent political groups, this cyberattack could show who runs these forums, which are now very important for alt-right movements.

Several leaked email addresses were contacted by TechCrunch, and a discussion was held with the individual associated with one of them. A 4chan moderator, choosing to remain anonymous, conveyed to TechCrunch their strong conviction regarding the authenticity of the leaked data and accompanying screenshots.

"I have no cause to believe otherwise," the janitor stated.

"I'm quite surprised," the administrator told TechCrunch. "4chan's moderation team has had leaks before, but this is clearly a much bigger problem. I'm not happy about this, and I'm sure most other people aren't either. But many of us have been doing this for a long time. People revealing private information about others has always been common on 4chan, and we've always known there was a chance we could be exposed."

"I've been most worried about the leaked information, for clear reasons," said the janitor. "I think that the fact that 4chan was basically taken over by a hacker or hackers is probably worse than just screenshots, at least for the site to keep working."

According to the administrator, it seems the hacker acquired the personal data of 4chan Pass subscribers, users who compensate the website to circumvent post restrictions and gain entry to an exclusive forum.

4chan provided no response to an email soliciting comment sent to the platform's press email address.

4chan is an online forum where people can post anonymously, and it is often seen as the internet's dark side. It is mostly an image board where bored users try to shock each other by posting very offensive content. Sometimes, things from 4chan appear in the real world as simple memes or as hateful ideas that encourage right-wing violence.

Memes like Pepe the Frog, rage comics, and wojaks first became popular on 4chan and are now seen everywhere online. But 4chan's biggest influence comes from its political sections, where extreme right-wing ideas can turn young people into white supremacists. QAnon, a group of far-right conspiracy theorists who support President Donald Trump, started on 4chan.

The person who shot and killed 51 people at two mosques in Christchurch, New Zealand, in 2019 had used 4chan regularly since he was a teenager. In 2022, an 18-year-old man killed 10 Black people at a grocery store in Buffalo, New York. His 180-page written statement used ideas from the Christchurch shooter's online writings.