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Remote Code Execution on a Facebook server

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Re: Remote Code Execution on a Facebook server

#111
post #61

Earlier quoted context omitted.

Funnily enough, it is mostly .NET applications running in production that I see stack-traces from these days.

If you even know something is a .Net app then the developer is likely terrible, so it is a self-selecting sample. You don't know most of the .Net MVC apps you interact with because there's no reason to know that.

This is really discriminatory and arrogant.

I used to feel the same way. It’s worth changing.

Re: Remote Code Execution on a Facebook server

#112
post #96

Earlier quoted context omitted.

No one talks about the working parts of security. Like, in this case, having the application on a separate box, and having that box separated by vlans from important things.

I don't think the solution is to put things you don't care about behind vlans and having applications on separate boxes. This box is/was an attack vector. It was holding secrets. Secrets provide other attack vectors.

It is - it is defense in depth. The application should be secure, and there should be steps to secure it. Especially because a secure application can protect a less secure network setup.

But on the other hand, the server or the network should not trust the application to be secure at all. The infrastructural setup should assume the application to be an . And that's why the application should be isolated on a system level, on a network level, and as much as possible. That's the good part I mean - the part that worked.

Re: Remote Code Execution on a Facebook server

#113
post #5

In contrast, I submitted a bad vulnerability in Facebook’s password reset feature yesterday that lets attacker’s send password reset PIN numbers to email addresses the user doesn’t necessarily control. The security team said to works as designed so they’re not going to fix it. Basically if someone requests a password reset on your account then the PIN number gets sent to all email addresses associated with your accou…

[deleted]

Re: Remote Code Execution on a Facebook server

#114

> scanning an IP range that belongs to Facebook (199.201.65.0/24) ping -4 facebook.com results in 157.240.18.35. Maybe, author used some other way to get those IPs. Can anyone throw a light on this?

You're going to get different results for the same queries depending on where you are in terms of DNS queries. This is not a FB thing, either. Lots of places will "steer" you towards one frontend, POP, datacenter, or whatever, in order to get you off the public Internet and onto their fabric sooner.

Run the same query from a bunch of sites with different connectivity in the same town and you might get different answers depending on who's got peering agreements with who. Then spin that query again using other places in the world and you can get even more variety.

That is, assuming the site in question has worked out a way to vary the A/AAAA records for their actual domain (as opposed to the hosts within it, like "www"). Some of them might just point it at a single POP/frontend/whatever, and when that one goes down for whatever reason... things get interesting. Not that I would know anything about that.

Re: Remote Code Execution on a Facebook server

#115

He got $5k for an arbitrary remote execution bug? What a rip-off.

He should have gone to the black market, better yet sat on it. How long did it take Facebook to come forward with its user privacy violations?

What would you guess the going rate on the black market would be for an RCE on some error-log collection box that happens to be in use by Facebook? My guess is "less than $5000".

Re: Remote Code Execution on a Facebook server

#116

This is a great concrete example why you should never run debug mode on a public server. Django can only do so much for redacting private info. This is also a great example of how insecure pickle is!

Exactly.. i think you often see a warning about pickle when it comes to safety. For example, the current documentation has a big, red warning right at the top: https://docs.python.org/3/library/pickle.html

The Django project also has a lot of warnings about the pickle serializer: https://docs.djangoproject.com/en/2.1/topics/http/sessions/

Re: Remote Code Execution on a Facebook server

#117
post #61

Earlier quoted context omitted.

Funnily enough, it is mostly .NET applications running in production that I see stack-traces from these days.

If you even know something is a .Net app then the developer is likely terrible, so it is a self-selecting sample. You don't know most of the .Net MVC apps you interact with because there's no reason to know that.

That's true for basically every stack

Re: Remote Code Execution on a Facebook server

#118
post #73

Earlier quoted context omitted.

The point is, "for fun and profit" is such an overused and utterly boring cliché. Meaningful titles are pleasant to read and shows that the writer has put some effort to bring clarity into what they're trying to convey. (As someone who sits on a major open source conference talk panel, I cringe when I see one of these clichés slapped into the title without much thought. I politely suggest to rephrase to convey more "…

I'm in absolute agreement. Nerd-culture has been on autopilot for decades and needs to find its next level.

Memes are the next level, it seems

Re: Remote Code Execution on a Facebook server

#119
post #61

Earlier quoted context omitted.

Funnily enough, it is mostly .NET applications running in production that I see stack-traces from these days.

If you even know something is a .Net app then the developer is likely terrible, so it is a self-selecting sample. You don't know most of the .Net MVC apps you interact with because there's no reason to know that.

Ever heard of Jon Skeet?

Re: Remote Code Execution on a Facebook server

#120
This is a good example why you need regular pentests in big companies. Everyone (should) know that using pickle is insecure and everyone (should) know that django debug should be False in production. Still, if the numbers get large enough someone will miss something.
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