Day: December 6, 2024

This Week In Security: National Backdoors, Web3 Backdoors, And Nearest Neighbor WiFi

December 6, 2024 by 16 Comments

Maybe those backdoors weren’t such a great idea. Several US Telecom networks have been compromised by a foreign actor, likely China’s Salt Typhoon, and it looks like one of the vectors of compromise is the Communications Assistance for Law Enforcement Act (CALEA) systems that allow for automatic wiretapping at government request.

[Jeff Greene], a government official with the Cybersecurity and Infrastructure Security Agency (CISA), has advised that end-user encryption is the way to maintain safe communications. This moment should forever be the touchstone we call upon when discussing ideas like mandated encryption backdoors and even the entire idea of automated wiretapping systems like CALEA. He went on to make a rather startling statement:

I think it would be impossible for us to predict a time frame on when we’ll have full eviction

There are obviously lots of unanswered questions, but with statements like this from CISA, this seems to be an extremely serious compromise. CALEA has been extended to Internet data, and earlier reports suggest that attackers have access to Internet traffic as a result. This leaves the US telecom infrastructure in a precarious position where any given telephone call, text message, or data packet may be intercepted by an overseas attacker. And the FCC isn’t exactly inspiring us with confidence as to its “decisive steps” to fix things. Continue reading “This Week In Security: National Backdoors, Web3 Backdoors, And Nearest Neighbor WiFi” →

Hacked Ultrasonic Sensors Let You See With Sound

December 6, 2024 by 13 Comments

If you want to play with radar — and who could blame you — you can pretty easily get your hands on something like the automotive radar sensors used for collision avoidance and lane detection. But the “R” in radar still stands for “Radio,” and RF projects are always fraught, especially at microwave frequencies. What’s the radar enthusiast to do?

While it’s not radar, subbing in ultrasonic sensors is how [Dzl] built this sonar imaging system using a lot of radar principles. Initial experiments centered around the ubiquitous dual-transducer ultrasonic modules used in all sorts of ranging and detection project, with some slight modifications to tap into the received audio signal rather than just using the digital output of the sensor. An ESP32 and a 24-bit ADC were used to capture the echo signal, and a series of filters were implemented in code to clean up the audio and quantify the returns. [Dzl] also added a downsampling routine to bring the transmitted pings and resultant echoes down in the human-audible range; they sound more like honks than pings, but it’s still pretty cool.

To make the simple range sensor more radar-like, [Dzl] needed to narrow the beamwidth of the sensor and make the whole thing steerable. That required a switch to an automotive backup sensor, which uses a single transducer, and a 3D printed parabolic dish reflector that looks very much like a satellite TV dish. With this assembly stuck on a stepper motor to swivel it back and forth, [Dzl] was able to get pretty good images showing clear reflections of objects in the lab.

If you want to start seeing with sound, [Dzl]’s write-up has all the details you’ll need. If real radar is still your thing, though, we’ve got something for that too.

Thanks to [Vanessa] for the tip.

Non-Planar Fuzzy Skin Textures Improved, Plus A Paint-On Interface

December 6, 2024 by 4 Comments

If you’ve wanted to get in on the “fuzzy skin” action with 3D printing but held off because you didn’t want to fiddle with slicer post-processing, you need to check out the paint-on fuzzy skin generator detailed in the video below.

For those who haven’t had the pleasure, fuzzy skin is a texture that can be applied to the outer layers of a 3D print to add a little visual interest and make layer lines a little less obvious. Most slicers have it as an option, but limit the wiggling action of the print head needed to achieve it to the XY plane. Recently, [TenTech] released post-processing scripts for three popular slicers that enable non-planar fuzzy skin by wiggling the print head in the Z-axis, allowing you to texture upward-facing surfaces.

The first half of the video below goes through [TenTech]’s updates to that work that resulted in a single script that can be used with any of the slicers. That’s a pretty neat trick by itself, but not content to rest on his laurels, he decided to make applying a fuzzy skin texture to any aspect of a print easier through a WYSIWYG tool. All you have to do is open the slicer’s multi-material view and paint the areas of the print you want fuzzed. The demo print in the video is a hand grip with fuzzy skin applied to the surfaces that the fingers and palm will touch, along with a little bit on the top for good measure. The print looks fantastic with the texture, and we can see all sorts of possibilities for something like this.

Continue reading “Non-Planar Fuzzy Skin Textures Improved, Plus A Paint-On Interface” →