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ArcHound | on: Broccoli2Shell: Brotli decoder RCE in Node.js, Python and more
I think the issue is that the servers "silently" support brotli. Then nobody uses it, but the attacker can still abuse the feature.

So as a hotfix I block this on my reverse proxy.

bawolff | parent | next
But is that actually true?

It seems like node supports it with body parser enabled.

But im having trouble finding any docs suggesting anything else supports it on inbound requests.

Obviously there are other scenarios where it is exploitable, but it is a much less severe vuln if the attacker must first force the program to make an outbound request to a server of its chosing rather than just connect to a vulnerable server.

ArcHound | root | parent | next
The idea is to identify brotli encoding in the content-encoding header and block that on nginx. This shouldn't reach vulnerable brotli parser in node.

I hope my assets are not connecting to malicious servers, otherwise yes, I have a problem.

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AlienRobot | parent | next
I wonder if we'll see more of this thanks to AI. Extremely complex features that nobody uses and that were easy to add, which incidentally tremendously expand the attack surface. One would hope that maintainer would be wise to avoid that, but for how long?
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ArcHound | root | parent
I think so, especially vibe coded software. I think hackers have the advantage now and defenders need to limit attack surface more rigorously.

Unfortunately that means understanding and limiting dependencies of developers... Yea, good luck.

My popcorn is ready. My servers are not.

whoanoway | root | parent
I'm not saying that my experience translates 1:1. As a child of domestic violence, all I can say is that it never gets better. Sadly, my feeling is that the violence will only escalate from here. If you look at the bright side, you can earn your stripes as a legitimate infosec engineer and prove your worth to the industry and the world.
ArcHound | root | parent
I'm sorry that happened to you. I tend to agree that the race to the bottom will continue.

And don't worry about my stripes, I'm mostly talking about my hobby self-hosted apps. If anything, should someone hack them I'll have a funny article to post on my blog. Professionally, I do things differently.

bflesch | parent
Cloudflare has this amazing feature where it accepts compressed payloads and forwards them to unsuspecting backends. Can be weaponized in many ways.