This Week In Security: PostHog, Project Zero Refresh, And Thanks For All The Fish

There’s something immensely satisfying about taking a series of low impact CVEs, and stringing them together into a full exploit. That’s the story we have from [Mehmet Ince] of Prodraft, who found a handful of issues in the default PostHog install instructions, and managed to turn it into a full RCE, though only accessible as a user with some configuration permissions.

As one might expect, it all starts with a Server Side Request Forgery (SSRF). That’s a flaw where sending traffic to a server can manipulate something on the server side to send a request somewhere else. The trick here is that a webhook worker can be primed to point at localhost by sending a request directly to a system API.

One of the systems that powers a PostHog install is the Clickhouse database server. This project had a problem in how it sanitized SQL requests, namely attempting to escape a single quote via a backslash symbol. In many SQL servers, a backslash would properly escape a single quote, but Clickhouse and other Postgresql servers don’t support that, and treat a backslash as a regular character. And with this, a read-only SQL API is vulnerable to SQL injection.

These vulnerabilities together just allow for injecting an SQL string to create and run a shell command from within the database, giving an RCE and remote shell. The vulnerabilities were reported through ZDI, and things were fixed earlier this year. Continue reading “This Week In Security: PostHog, Project Zero Refresh, And Thanks For All The Fish”

ABB arm printing a vase

Surplus Industrial Robot Becomes Two-ton 3D Printer

As the saying goes — when life gives you lemons, you make lemonade. When life gives you a two-ton surplus industrial robot arm, if you’re [Brian Brocken], you apparently make a massive 3D printer.

The arm in question is an ABB IRB6400, a serious machine that can sling 100 to 200 kilograms depending on configuration. Compared to that, the beefiest 3D printhead is effectively weightless, and the Creality Sprite unit he’s using isn’t all that beefy. Getting the new hardware attached uses (ironically) a 3D printed mount, which is an easy enough hack. The hard work, as you might imagine, is in software.

As it turns out, there’s no profile in Klipper for this bad boy. It’s 26-year-old controller doesn’t even speak G-code, requiring [Brian] to feed the arm controller the “ABB RAPID” dialect it expects line-by-line, while simultaneously feeding G-code to the RAMPS board controlling the extruder. If you happen to have the same arm, he’s selling the software that does this. Getting that synchronized reliably was the biggest challenge [Brian] faced. Unfortunately that means things are slowed down compared to what the arm would otherwise be able to do, with a lot of stop-and-start on complex models, which compromises print quality. Check the build page above for more pictures, or the video embedded below.

[Brian] hopes to fix that by making better use of the ABB arm’s controller, since it does have enough memory for a small buffer, if not a full print. Still, even if it’s rough right now, it does print, which is not something the engineers at ABB probably ever planned for back before Y2K. [Brian]’s last use of the arm, carving a DeLorean out of styrofoam, might be closer to the original design brief.

Usually we see people using 3D printers to build robot arms, so this is a nice inversion, though not the first.

Continue reading “Surplus Industrial Robot Becomes Two-ton 3D Printer”

Windmill Desk Lamp Is Beautifully Soothing

Typically, lamps provide a stationary source of light to illuminate a given area and help us see what we’re doing. However, they can also be a little more artistic and eye-catching, like this windmill lamp from [Huy Vector].

It’s somewhat of a charming desk toy, constructed out of copper wire soldered into the form of a traditional windmill. At its base, lives a simple motor speed controller, while up top, a brushed DC gearmotor is responsible for turning the blades. As you might imagine, it’s a little tricky to get power to flow to the LED filaments installed on those blades while they happen to be rotating. That’s where the build gets tricky, using the output shaft of the motor’s gear drive and a custom slip ring to pass power to the LEDs. That power comes courtesy of a pair of 16340 lithium-ion cells, which can be juiced up with the aid of a USB-C charger board.

It’s an elegant build, and rather charming to watch in motion to boot. We love a good lamp build here at Hackaday, particularly when they’re aesthetically beautiful.

Continue reading “Windmill Desk Lamp Is Beautifully Soothing”