Live data from Hacker News

Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

arnaucode.com

21–30 of 56 posts

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#21

Earlier quoted context omitted.

New users are green, iirc 50 or 100 karma points required to get normal grey

Feels like they are more superior than us based on his color.

In English being "green" can mean being "new," like a sapling or new shoots on a plant, which are often bright green.

I don't know for sure if that's why they chose to make new users green but that's how I view it.

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#22
post #2

I've thought about adding something like this to my guest wifi to mine some cryptocurrency - but quickly dismissed it as most guests would need to use a charger soon(ish) and thus using my electricity :P

let's submit patches that mine coins, with the recent 30% perf drop thanks to meltdown people won't notice

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#23

Earlier quoted context omitted.

It's also a scummy thing to do and sets a terrible precedent. Do you want friendly customers on your WiFi or do you want angry customers who feel cheated when they learn the truth?

I think it was basically a joke, and I think his "guests" are friends, not customers, and would therefore be likely to appreciate the joke even if he actually did it.

Ah, okay :)

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#24
post #13

Earlier quoted context omitted.

If you control the AP, you should disallow client to client communication. Most AP's and routers allow this and it would mitigate this risk.

Is there any way to mitigate this without limiting abilities of people on the network? It kind of destroys the point of a LAN.

don't take my word for it, but I'd bet you could disallow LAN comms on port 80 and prevent this. Typically a toxic client would flood the arp table until the router believed the toxic client should receive all communications and then the toxic client would mitm and forward traffic on the expected port to other normal clients...if the toxic client can't send stuff on port 80 to a normal client they can't easily mitm them

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#26
post #13

Earlier quoted context omitted.

If you control the AP, you should disallow client to client communication. Most AP's and routers allow this and it would mitigate this risk.

Is there any way to mitigate this without limiting abilities of people on the network? It kind of destroys the point of a LAN.

Did you ever use LAN functionalities in public Wifi (e.g. Starbucks)?

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#27
post #7

Excellent write up. That’s why we need SSL/TLS with HSTS. Pure HTTP, specially in public WiFi, is dead.

Since we won't get https everywhere soon, is WPA2 on a public Wifi with a publicly known key a workaround? Should prevent plain MITM?

Honestly any decent public wifi setup even if it isn't going to limit client to client communication, if that's needed for some reason, should be restricting based on protocol/port/etc. It should be a whitelist, not a blacklist. There's no reason a client should be able to touch HTTP traffic towards anything but the gateway.

This is trivial to set up with for example, even a cheap sonicwall.

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#28
post #7

Excellent write up. That’s why we need SSL/TLS with HSTS. Pure HTTP, specially in public WiFi, is dead.

Since we won't get https everywhere soon, is WPA2 on a public Wifi with a publicly known key a workaround? Should prevent plain MITM?

> is WPA2 on a public Wifi with a publicly known key a workaround?

You're thinking of packet injection (or data intercept) by any nearby individual, which WPA2 with known PSK would mitigate. However, as an attacker would know the PSK, they could simply join the network to side-step this.

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#29
Given the recently disclosed vulnerabilities, instead of a cryptocurrency miner, it could be a Spectre exploit trying to scan and exfiltrate data from the computer's memory. We might be now at the point where disabling all Javascript for non-HTTPS pages is a good default.

Re: Hacking WiFi to inject cryptocurrency miner to HTML requests (CoffeeMiner)

#30

Some buildings (hostels and shared accomodations) have shared internet (secured with WPA2). This type of attack might be particularly profitable in such situations.

Wouldn't WPA2 protect users from an attack like this?
Post reply on HN