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Spam Supposedly from Facebook Friends

Nov 21st, 2012
by Jeff Duntemann.
4 comments

As mysteries go this was small change, but I stumbled across its solution earlier today: spam nominally from Facebook friends. I’ve been getting a recognizable species of link spam every day or two for a couple of months now. The From: field always contains the name of someone I know. The From: email address, however, is unknown to me and does not belong to the person named. The Subject: field is short and nondescript, like “Hello”. The body of message is brief and follows this form:

super http://spammityspam.spam/goosebrow/53zappovat/

11/21/2012 10:33:27 AM

The From: email address is always a gobbledegook address from a big email service like Hotmail or AOL. There may be two or three words before the link, but no more than that. The link destination is different every time. I don’t know, don’t care, and don’t intend to find out what’s at the other end of the links.

I first assumed that someone I knew had gotten his or her address book hijacked by a trojan, which has long been a common practice when a machine is hacked. The interesting thing was that many of the people didn’t know one another at all. (I asked a few of them.) My next thought was that my own address book had been hijacked, except that two other people (out of eight or nine spams that I had tucked away to examine) were folks for whom I did not have and never had an email address. It took awhile for me to realize that the only common element was their presence in my Facebook friends list.

Bingo.

I sniffed around and found a nice description of the problem on CNET. In short, there was a Facebook vulnerability that allowed a scraper to lift the names (but not the email addresses, nor any private information) from my facebook friends list. Facebook has fixed the vulnerability, or claims to have fixed it. Facebook being Facebook, however, I’m sure there are plenty of others down there in the morass.

Given that over half of the posts in a recent sample of my friends feed today were idiotic or hate-filled images (many images consisting solely of words, which is idiocy cubed, and sometimes words too small to read, which is idiocy to the seventeenth power) I wonder sometimes why I bother.

A Steampunk Aethernet Concentrator

May 27th, 2011
by Jeff Duntemann.
6 comments

Concentrator500Wide.jpg

Those who tuned in to my March 18, 2011 entry will recall that I spotted a Star-Rite copper parabolic resistance heater at a consignment store, and brought it home thinking it would make a good Wi-Fi antenna. I put a proof-of-concept lashup together last week and found that it worked very well, even though its diameter is on the low side for 13 cm microwaves. I spent half an hour or so digging through my several bins of odd plastic looking for just the right center insert, and stumbled on a pill bottle that ProbeExposed200Wide.jpgactually pressure-fit into the center hole without any modifation of the bottle or the center hole. (This may seem remarkable if you’ve never seen the quanity of pill bottles and other odd plastic (s)crap I keep out in the garage.)

The Wi-Fi element is a Cisco AE1000 USB 2.0 Wi-Fi adapter, connected to the PC through a 3′ USB extension cable. The female end of the extension cable is glued into a rectangular hole I made in the pill bottle’s white lid with a nibbling tool, and the AE1000 plugs into the adapter cable.

Even with the number of pill bottles I have, finding this particular bottle was a huge break. I still have to figure a way to get the probe fastened into the hole by something better than friction, but that’s just engineering. The bottle works extremely well for another simple but fortuitous reason: It puts the long axis of the AE1000 right where the focus of the copper parabola falls.

I tested for this out in the driveway in an interesting way: I pointed the parabola at the Sun as closely as I could, and then stuck a paper towel tube into the center hole to see where the sunlight would be most intense. The strongest part of the focus is about 3″ from the bottom of the bowl. (I didn’t leave the paper towel tube at the focus for very long, trust me.) This is just about where the AE1000’s antennas sit, if its interior construction is anything like the USB Wi-Fi dongle I sacrified some years back to see how it was done.

FocusTest350Wide.jpgFor as lucky as I got, the position of the adapter isn’t especially critical. We’re not trying to create an image or even intense heat. We’re just trying to concentrate a distant microwave signal on the AE1000, and focus the signal that it emits into a narrower steerable beam. Nor am I going for moonbounce–the real mission of the device is to make sure I can get into the resort Wi-Fi access points when I’m at the Taos Toolbox writers’ workshop this summer. That always depends on where your room is relative to the access points, and in the past, I’ve pulled rooms in dead spots about two throws out of five.

Well, not this time.

Jim Strickland suggested calling it an Aethernet Concentrator, and so it is. (The name of the Wi-Fi adapter is peculiarly appropriate.) I’m not entirely finished yet. I need to paint the pill bottle so that it looks less like a pill bottle, and the copper bowl needs cleaning and polishing generally. But I’ve already tested it, and it increases the strength of my access point downstairs radically. Aiming it up and down the street from here at my desk, it detected nine APs that the naked AE1000 didn’t see plugged into the back of my GX620. (I call this “warsitting.”)

I’m going to do a larger article on the project once I tie the ribbons on it, and I’ll let you know where to find it when I do.