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4chan Sharty Hack And Janitor Email Leak

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Re: 4chan Sharty Hack And Janitor Email Leak

#411

Post by ranger_danger »

robotnikman wrote: post #397

I did some digging and the hacker posted which exploit he used. Apparently some boards allowed uploading PDF files, but the site never checked if the PDF file was an actual PDF file. Once a PDF file was uploaded it was passed to a version of Ghostscript from 2012 which would generate a thumbnail. So the attacker found an exploit where uploading a PDF with the right PostScript commands could give the attacker shell ac…

Why would you say how you did it? Now they can't do it all over again when it comes back /s

Re: 4chan Sharty Hack And Janitor Email Leak

#412

Post by Klonoar »

shadowgovt wrote: post #372
amadeuspagel wrote: post #241

Earlier quoted context omitted.

"Not your personal army" goes father then not doxxing. It's a rejection of any attempt to imagine a community of strangers, united by hatred of a scapegoat.

If someone rallied a hate-mob on 4chan, though, how would people know? Since 4chan overtly resists it, it'd rapidly move off of there, but it's still a great place to find like-minded folks that'd follow someone to another server to go brigade someone.

4chan has always claimed to resist it, but 4chan was never immune to being shuffled a specific way.

Re: 4chan Sharty Hack And Janitor Email Leak

#413

Post by busterarm »

_345 wrote: post #238
eqvinox wrote: post #213

Earlier quoted context omitted.

I always thought it's /b/ that people conflate with the whole website… (for the purpose of declaring it a cesspool) … but then again I never looked at /pol/, maybe it's even worse than /b/?

it is, and unfortunately from 2016 onwards it kind of outgrew the rest of the site like a tumorous growth until the whole site became markedly more neonazi and less goofy. something to do with donald trump i suspected

the fash trend on /pol/ died somewhere around 2018 and has shifted significantly radleft in the years since. This is misunderstood by outsiders largely because /pol/ users don't actually hold these opinions, they just will represent whatever is the edgiest opinion at any given time.

And despite things like shooting pharma executives in broad daylight being mainstream now, /pol/lacks rightly recognize that this is still edgy upon edgy upon edgy. And thus they meme the shit out of it.

Re: 4chan Sharty Hack And Janitor Email Leak

#414

Post by 6LLvveMx2koXfwn »

ethbr1 wrote: post #249
cwmma wrote: post #225

Earlier quoted context omitted.

For the record this is an example of the "Fencepost error" where the last item in a range gets double counted as the first item in the next range and is incredibly common in dyscalculia (the math version of dyslexia) as people will have "visual number lines" in their head that cover ranges of numbers but the ends get double counted, so there will be a 10-20 number line then a 20-30 number line. I suspect TheJosh had…

As the quip goes, there are two hard problems in computer science: cache invalidation, naming things, and off-by-one errors.

That's three though.

Re: 4chan Sharty Hack And Janitor Email Leak

#415

Post by 0x303 »

robotnikman wrote: post #397

I did some digging and the hacker posted which exploit he used. Apparently some boards allowed uploading PDF files, but the site never checked if the PDF file was an actual PDF file. Once a PDF file was uploaded it was passed to a version of Ghostscript from 2012 which would generate a thumbnail. So the attacker found an exploit where uploading a PDF with the right PostScript commands could give the attacker shell ac…

Got a source? Not doubting, just curious.

Re: 4chan Sharty Hack And Janitor Email Leak

#417

Post by loves_mangoes »

robotnikman wrote: post #397

I did some digging and the hacker posted which exploit he used. Apparently some boards allowed uploading PDF files, but the site never checked if the PDF file was an actual PDF file. Once a PDF file was uploaded it was passed to a version of Ghostscript from 2012 which would generate a thumbnail. So the attacker found an exploit where uploading a PDF with the right PostScript commands could give the attacker shell ac…

That checks out. Years ago I noticed a vulnerability through the photography board. You'd upload your pictures, and 4chan would display all the EXIF info next to the post.

4chan's PHP code would offload that task to a well-know, but old and not very actively maintained EXIF library. Of course the thing with EXIF is that each camera vendor has their own proprietary extensions that need to be supported to make users happy. And as you'd expect from a library that parses a bunch of horrible undocumented formats in C, it's a huge insecure mess.

Several heap overflows and arbitrary writes all over the place. Heap spray primitives. Lots of user controlled input since you provide your own JPEG. Everything you could want.

So I wrote a little PoC out of curiosity. Crafted a little 20kB JPG that would try to allocate several GBs worth of heap spray. I submit my post, and the server dutifully times out.

And that's where I'd like to say I finished my PoC and reported the vulnerability, but in fact I got stuck on a reliable ASLR bypass and lost interest (I did send an email about the library, but I don't think it was actively maintained and there was no followup)

My impression from this little adventure is that 4chan never really had the maintenance and code quality it needed. Everything still seemed to be the same very old PHP code that leaked years ago (which included this same call to the vulnerable EXIF library). Just with a bunch of extra features hastily grafted and grown organically, but never dealing with the insane amount of technical debt.

Re: 4chan Sharty Hack And Janitor Email Leak

#418

Post by GuinansEyebrows »

wegfawefgawefg wrote: post #120
brigandish wrote: post #98

I see a lot of hate for 4chan here. Why? I’ve never used it, know it by reputation, but not sure why there’s so much hate for it.

[flagged]

Certainly has nothing to do with the toxic userbase of at least some of the boards

Re: 4chan Sharty Hack And Janitor Email Leak

#419

Post by greazy »

Blikkentrekker wrote: post #206
greazy wrote: post #134

4chan is a reflection of the depraved, extreme side of humanity. Twitter has taken on the mantle of 'asshole of the internet', but I think the rotten apples post in both. 4chan is oddly accepting of gay and trans people. I've seen gay and trans porn side by side with bbc and bwc porn posts. Strange to see racist trans porn lovers. I like 4chan for the minor boards, not /pol/ or /b/. But /boardgames/ and /dyi/ and /in…

> 4chan is oddly accepting of gay and trans people. I've seen gay and trans porn side by side with bbc and bwc porn posts. Strange to see racist trans porn lovers. It only seems odd because many people interpret this through a U.S.A. “culture war” lens and “gay people”. You believe they're “accepting of gay people” in the sense of that culture war because of the “gay porn”. In reality, they take more of a classical G…

I should have used a better example to support my point.

I was referring to the website it self allowing gay and trans content, and even other non mainstream content (furry, MLP). The content is not just porn related (though a big chunk of it is).

On the porn front, I don't agree with liking 'lady dick' twink lovers only. There's 'normal' gay content (male on male).

On the non porn content, lots of posts will begin with 'Im a gayfag' (fag here I used as a catch all self deprecating term, some users will say I'm a oldfag, even seen ladyfag). Never seen any outright harassment of gay people when they post.

Having said that, there is straight gay, trans, minority hating posts and content.

4chan is a wild jungle. Or was.

Re: 4chan Sharty Hack And Janitor Email Leak

#420

Post by robotnikman »

0x303 wrote: post #415
robotnikman wrote: post #397

I did some digging and the hacker posted which exploit he used. Apparently some boards allowed uploading PDF files, but the site never checked if the PDF file was an actual PDF file. Once a PDF file was uploaded it was passed to a version of Ghostscript from 2012 which would generate a thumbnail. So the attacker found an exploit where uploading a PDF with the right PostScript commands could give the attacker shell ac…

Got a source? Not doubting, just curious.

search through the thread on the site where that attack came from. ctrl+f postscript and you will find the post
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