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Top 10 Most Obvious Hacks of All Time (v0.9)

For teaching hacking/cybersecurity, I thought I'd create of the most obvious hacks of all time. Not the best hacks, the most sophisticated hacks, or the hacks with the biggest impact, but the most obvious hacks -- ones that even the least knowledgeable among us should be able to understand. Below I propose some hacks that fit this bill, though in no particular order.

The reason I'm writing this is that my niece wants me to teach her some hacking. I thought I'd start with the obvious stuff first.


Shared Passwords

If you use the same password for every website, and one of those websites gets hacked, then the hacker has your password for all your websites. The reason your Facebook account got hacked wasn't because of anything Facebook did, but because you used the same email-address and password when creating an account on "beagleforums.com", which got hacked last year.

I've heard people say "I'm sure, because I choose a complex password and use it everywhere". No, this is the very worst thing you can do. Sure, you can the use the same password on all sites you don't care much about, but for Facebook, your email account, and your bank, Continue reading

Is DefCon Wifi safe?

DEF CON is the largest U.S. hacker conference that takes place every summer in Las Vegas. It offers WiFi service. Is it safe?

Probably.

The trick is that you need to download the certificate from https://wifireg.defcon.org and import it into your computer. They have instructions for all your various operating systems. For macOS, it was as simple as downloading "dc25.mobileconfig" and importing it.

I haven't validated the DefCon team did the right thing for all platforms, but I know that safety is possible. If a hacker could easily hack into arbitrary WiFi, then equipment vendors would fix it. Corporations widely use WiFi -- they couldn't do this if it weren't safe.

The first step in safety is encryption, obviously. WPA does encryption well, you you are good there.

The second step is authentication -- proving that the access-point is who it says it is. Otherwise, somebody could setup their own access-point claiming to be "DefCon", and you'd happily connect to it. Encrypted connect to the evil access-point doesn't help you. This is what the certificate you download does -- you import it into your system, so that you'll trust only the "DefCon" access-point that has Continue reading

Slowloris all the things

At DEFCON, some researchers are going to announce a Slowloris-type exploit for SMB -- SMBloris. I thought I'd write up some comments.


The original Slowloris from several years creates a ton of connections to a web server, but only sends partial headers. The server allocates a large amount of memory to handle the requests, expecting to free that memory soon when the requests are completed. But the requests are never completed, so the memory remains tied up indefinitely. Moreover, this also consumes a lot of CPU resources -- every time Slowloris dribbles a few more bytes on the TCP connection is forces the CPU to walk through a lot of data structures to handle those bytes.

The thing about Slowloris is that it's not specific to HTTP. It's a principle that affects pretty much every service that listens on the Internet. For example, on Linux servers running NFS, you can exploit the RPC fragmentation feature in order to force the server to allocate all the memory in a box waiting for fragments that never arrive.

SMBloris does the same thing for SMB. It's an easy attack to carry out in general, the only question is how much resources are required Continue reading
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