Submitted 23 hours ago by Tea@programming.dev to technology@lemmy.world
https://www.tarlogic.com/news/backdoor-esp32-chip-infect-ot-devices/
Tarlogic Security has detected a backdoor in the ESP32, a microcontroller that enables WiFi and Bluetooth connection and is present in millions of mass-market IoT devices. Exploitation of this backdoor would allow hostile actors to conduct impersonation attacks and permanently infect sensitive devices such as mobile phones, computers, smart locks or medical equipment by bypassing code audit controls.
Please update the title of this post to mention the update
How so?
Idk maybe specify that it was determined to not be a backdoor. Right now it reads as anti-china fear mongering.
This isn’t a backdoor. Just a company trying to make name for themselves by sensationalizing a much smaller discovery.
Seriously this. Every single IC which has digital logic contains some number of undocumented test commands used to ensure it meets all the required specifications during production. They’re not intended to be used for normal operation and almost never included in datasheets.
If anyone’s ever followed console emulator development, they know those undocumented commands are everywhere. There’s still people finding new ones for the N64 hardware
Or use a precise title. It’s not a backdoor or a “backdoor”.
This turned racist / xenophobic real quickly.
There have been several other posts about this without mentioning China at all, especially in the post itself.
No where in the article does it say “chinese”, literally anywhere.
The chip is MANUFACTURED in China.
Check your racism.
I agree we shouldn’t be racist against Chinese people, but you’re ignorant. From wikipedia: ESP32 is created and developed by Espressif Systems, a Chinese company based in Shanghai, and is manufactured by TSMC using their 40 nm process.It is a successor to the ESP8266 microcontroller.
Dog whistling.
This has nothing to do with the chip or who makes it.
It’s the way it’s written.
You missed the point.
I actually wanted to keep the title short, but I think it would be better to edit the title to avoid any confusion to make it clear that it’s manufactured in China, rather than saying it in the current way.
So instead of blatant racism based on a lie, you’re just going to dogwhistle racism based on a lie.
Thank you, your explanation / edit is much appreciated 👏 🥳 ❤️
No. Fuck the Chinese. All 17billion of them.
/s
17billion of them.
Xi had a clone army?
🤔
Weird that they removed the reference to ESP32, one of the most common and widely known microcontrollers, from the headline.
This sounds like there are some undocumented opcodes on the HCI side – the Host Computer Interface – not the wireless side. By itself, it’s not that big a deal. If someone can prove that there’s some sort of custom BLE packet that gives access to those HCI opcodes wirelessly, I’d be REALLY concerned.
But if it’s just on the host side, you can only get to it if you’ve cracked the box and have access to the wiring. If someone has that kind of access, they’re likely to be able to flash their own firmware and take over the whole device anyway.
Not sure this disclosure increases the risk any. I wouldn’t start panicking.
So explained to me, a tech illiterate in comparison, this is China bad scaremongering?
‘Backdoor’ sounds malicious with intent.
Pull up a chair and pour yourself a stiff beverage…
TLDR: Don’t Panic.
If you have a regular old processor (MCU) and want to give it wireless capability, you can buy a wireless chip and stick it next to the processor, then have the MCU talk to it through a wired connection (typically UART or SPI). Think of it as the old ATDT commands that had your PC control your old screeching modems.
To standardize this communication protocol, folks came up with the Host Controller Interface (HCI) so you didn’t have to reinvent that protocol for every new chip. This was handy for people on the MCU side, since they could write firmware that worked with any wireless chip out there, and could swap out for a cheaper/faster one with minimal change.
Fast forward to the era of integrated MCU+wireless, where you had a little ARM or other lightweight processor plus a little radio, and the processor could run programs in a high-level API that abstracted out the low level wireless stuff. Plus, you could use the same radio for multiple wireless protocols, like BLE, wifi, ANT, etc. Nordic and TI were early adopters of this method.
Typically, it was the vendor’s own processor talking to their own wireless module, but they still implemented the full HCI interface and let it be accessed externally. Why? So if your design needed an extra beefy processor and used the MCU+wireless chip as a simple communication module, this would still work. The teeny MCU could be used to run something extra in parallel, or it could just sit idle. A typical example could be a laptop or cell phone. The little MCU is too small for everything else, so you pair it with a big chip and the big chip drives the little chip through HCI.
Sure, it would be cheaper if you just went with a basic ‘dumb’ wireless chip, as folks from CSR, Broadcom, and Dialog kept pointing out. But the market demanded integrated chips so we could have $10 activity trackers, fancy overpriced lightbulbs, and Twerking Santas (www.amazon.com/twerking-santa-claus/s?k=twerking+…).
For integrated MCU+wireless chips, most vendors didn’t release the super low-level firmware that ran between them. There was no need. It was internal plumbing. They exposed SDKs so you could control the wireless chip, or high-level Bluetooth/wifi APIs so you could connect and talk to the outside world in a few lines of code. These SDKs were unique to each vendor (like Nordic’s nRF Connect library, or TI’s SimpleLink SDK).
Then along came Espressif out of Shanghai, China with a combo chip (ESP8266) that offered processor + wifi and was so cheap and easy to program that it took the hobbyist market by storm. Oh, god… so many LED light strips, perfect for Christmas and blinky EDM lightup outfits (hello, Adafruit: www.adafruit.com/category/65).
Fast forward and Espressif drops the ESP32. A bigger, faster Tensilica Xtensa processor, with built-in flash storage, plus wifi, Bluetooth, and BLE in one place. Plus lots of peripherals, busses, and IO pins. Also, running FreeRTOS and eventually Arduino SDKs, and MicroPython. All for less than $5! It took off like a rocket. So many products. Plus, you could run them as little webservers. Who doesn’l love a little webserver in their pocket?
It’s gone through a few variations, including swapping out the Tensilica with an open-source RISC-V MCU, but otherwise it’s a massive seller and the gateway drug for most IoT/Smarthome nerds.
So along come these Tarlogic researchers, looking to build a direct USB to bluetooth library. This way, you can drive the wireless from, say Linux, directly. There are already BLE to USB stacks, but this one is giving access at the HCI level, in a C library. Handy if you’re doing research or developing drivers, but not the sort of thing your typical DIY pereon needs.
As part of their process, the researchers decide to dump the really low level ESP32 firmware and reverse engineer it.
A typical HCI implementation is a giant event loop that handles HCI opcodes and parameters. Host wants to talk to the outside world, it sets up some registers, configures the unique MAC address, then opens a channel and starts sending/receiving (hopefully without the modem screeching tones). There are typical packet encoders and decoders, multiple ISO/TCP layers, and the sort of thing that most people assume somebody else has gotten right.
For fancier implementations, there may be interrupt or DMA support. Sometimes, there’s a multi-tasking part under the hood so they can time-slice between wifi, bluetooth, and ble (aka Fusion or Coexistence support). Not that you should care. The internals of this stuff is usually nobody’s business and the vendors just include a binary blob as part of their SDK that handles things. The host systems just talk HCI. The wireless side talks HCI on the wired side, and wireless on the radio side. Everyone’s happy.
In the process of reverse engineering the low-level HCI blob, these researchers found a few extra undocumented HCI opcodes. They’re not sure what they’re for, but according to their presentation (documentcloud.org/…/25554812-2025-rootedcon-bluet…) if my super rusty Spanish holds up, it has to do with setting MAC addresses and handling low-level Link-Level Control Protocol communications (www.ellisys.com/technology/een_bt10.pdf).
Now in an of itself, this is no big deal. ESP32s already let you easily set your own temporary MAC address (randomnerdtutorials.com/get-change-esp32-esp8266-…), so there has to be a way to override the manufacturer one. And LLCP management is a totally geeky low-level thing that the MCU needs when handling wireless packets. There are perfectly good reasons why the opcodes would be there and why Espressif may not have documented them (for example, they could be used only during manufacturing QA).
So the original presentation is a teeny bit of an exaggeration. Yes, the opcodes exists. But are they nefarious? Should we stick all our ESP32s inside Faraday cages? Is this a secret plan for the CCP to remotely control our lights and plunge the world into chaos?
As I said before, ONLY if there’s a secret as-yet-undiscovered wireless handshake that gives remote wireless access to these (or really, pretty much any other published HCI opcode). That presentation most definitely doesn’t claim that.
To see if there is a REAL backdoor, you should wait for an analysis from fine professional wireless debugging vendors like Ellisys (starting models run $30K and up), Frontline, or Spanalytics.
Incidentally, Tarlogic, the group that put out that paper have their own BLE analyzer product (www.tarlogic.com/es/…/analizador-bluetooth-le/). They look to know their stuff, so they should know better than putting out clickbait-y hair-on-fire reports. But come on, who can resist a good CCP/backdoor headline? Will media run with this and blow it out of proportion? No way!
If you’ve read this far, you must safely be on your third drink or the edible’s just kicked in. Stop panicking, and wait until the pro sniffer and Bluetooth forum people give their opinions.
If it turns out there is an actual WIRELESS backdoor, then by all means, feel free to panic and toss out all your Smarthome plugs. Go ahead and revert to getting up and flicking on your light switch like a peasant. Have a sad, twerk-free Christmas.
But over a few undocumented HCI opcodes? Have another drink and relax.
Happy Sunday.
PS: controversy already up on wikipedia: en.m.wikipedia.org/wiki/ESP32
PPS: you may want to stock up on ESP32s for your light-up Christmas light project. Don’t be surprised if Espressif doesn’t get smacked with some hard tariffs or an outright ban, based on these ragebait headlines 🤷🏻♂️
The article is a security company trying to hype their company with a theoretical attack that currently has no hypothetical way to be abused
The China part just came from OP
Fukin dmnit! I just spent the last several months fine tuning a PCB design supporting this platform. I have , what i believe to be my last iteration, being sent to fab now. I have to look i to this. My solution isnt using bluetooth, so i dont know if im vulnerable.
The exploit requires physical access. It’s not exploitable in 99% of cases
Its not a backdoor, your most likely fine.
I hate it when an attacker who already has root access to my device gets sightly more access to the firmware. Definitely spin up a website and a logo, maybe a post in Bloomberg.
We really should be pushing for fully open source stack (firmware, os) in all iot devices. They are not very complicated so this should be entirely possible. Probably will need a EU law though.
Open source stack will not prevent this. It’s not even a backdoor, it’s functionality that these researches think should be hidden from programmers for whatever reason.
Open source devices would have this functionality readily available for programmers. Look at rtl-sdr, using the words of these researches, it has a “backdoor” where a TV dongle may be used to listen to garage key fobs gasp everyone panic now!
thats a very fair point, I had not seen anyone else make this one But the problem is that in this case, this functionality was entirely undocumented. I dont think it was intended for programmers.
Now if the firmware was open source, people would have gotten to know about this much sooner even if not documented. Also such functionality should ideally be gated somehow through some auth mechanism.
Also just like how the linux kernel allows decades old devices to be at the very least patched for security risks, open firmware would allow users of this chip to patch it themselves for bugs, security issues.
I 100% believe firmware should be open source no question about it. There’s so many devices out there especially phones and iot devices that just become e-waste because you can’t do anything with it once it’s not supported if it was open source and documented in some way then it could be used. I have like five cheap phones that I got because they were so cheap but once they lost support they’ve become completely useless even though they still work.
But then big companies wouldn’t be able to keep milking the consumer via planned obsolescence. Won’t somebody think of the shareholders?
This is about silicon. Undocumented instructions have just been found in it but they are not executable unless the ESP32’s firmware uses them. Firmware cannot be edited to use them unless you have an existing vulnerability such as physical access or insecure OTA in existing firmware (as far as researchers know).
Backdoored devices are useful for people who can impede that.
And the way EU is approaching privacy, surveillance and all such, - oh-hoh-ho, I don’t think there will be a EU law.
Yeah tons of weird little private softwares never get updates, but they aren’t making anyone money either
The other day someone posted in Canada community that Canada should stop using Tesla cars and import Chinese cars. I replied saying, “That’s like replacing one evil with another.” I was downvoted by a lot of people. I should’ve expected it cuz a lot of people have short term memory.
Because that’s not about privacy, that’s about the trade war. Retaliatory tariffs on US cars increase cost of cars for Canadians, as there are almost no car assembled in Canada. Reducing or eliminating tariffs on cars from China would lower cost of new cars for Canadians while keeping the tariffs up.
For privacy and security, not a single new car on the market is decent right now. That should be regulated, but that’s no concern for any politician at the moment.
Europe and its 50 car makers could also be considered instead of China…
CCP has backdoor into every tech that comes out of China. It’s not about just privacy. They control democracies based on shaping narratives. They’ll utilize everything that democracy offers and use it against countries. They don’t have freedom of speech or press so they themselves are not victims of it. EVs are really just computers on the road. Flooding the market with Chinese EVs would just mean creating a massive free network on a foreign soil for them.
A lot of people are dumb. Or maybe because they feel offended because they are Chinese, but the reality is that every Chinese company is ultimately controlled by the CCP.
Or maybe because they feel offended because they are Chinese
I’m Chinese-American and I’m not offended. The tankies from .ml are
the reality is that every Chinese company is ultimately controlled by the CCP.
Yes.
But in the same way that every US company is ultimately controlled by the US Government. And every EU company by them. And every other country by their own government.
“China bad” because western media says so. Please disregard the billions of dollars spent by western governments to ensure you keep thinking that way.
It’s just another capitalistic country no better or worse than Canada or the USA. Though, the Chinese government has said their intention is to move towards socialism, so good for them. I’m stuck over here witnessing fascist billionaires loot the government/working class.
Thats super interesting! Write a poem about three gorges dam please
No, ‘China bad’ because many many examples of China bad. Such as the topic of this post.
The whole “you can’t criticize China because you’re from a country that also does bad things” is logically worthless. It’s the argument of hypocrisy fallacy.
Not sure if you realize this but China is also ruled by a kleptocratic billionaire class that loots the working class even moreso than the US, so i’m not sure why you look up to them - China has more billionaires and a much larger wealth divide than the US. Actions speak louder than words and while Xi and the CCP often talk about cracking down on thier ultra-wealthy, they don’t really do much - couple billionaires might disappear occasionally though if they don’t praise the party line publically. One thing is for sure - I don’t see any elite CCP party members that are not also very wealthy. And it’s everyone else that’s propagandized 🤔
Well, no, China is bad because freedom is very restricted there and because they have ambitions to dominate the world.
Yes, every other world power in the world is more or less the same. People cannot, in general, be trusted to be “good” when given the opportunity to abuse. A world power can be held in check by the presence and efforts of other world powers, though.
China is bad, because they too are a colonialism and imperialistic nation.
Just like the US and Russia.
There’s been a lot of that lately. Same here in New Zealand.
You dipshits, they’re both the bad guys now.
Everyone has short-term memory and long-term memory. You’re misunderstanding precisely what “short term memory” refers to. Short-term memory is held for a short time before it’s converted to long-term memory. What you’re referring to is being short-sighted. As in people who don’t fully think about the long-term consequences of current actions. Said short-sighted people still have both short and long-term memory. They’re probably just a little dumb so they don’t fully utilize the memories stored long term.
Jesus. Okay. So when you say, “being short sighted”, you don’t literally mean they have myopia. You mean it figuratively. Exactly like the person you are correcting clearly means it figuratively when they say “short-term memory”.
People act like traditional car manufacturers don’t exist anymore even though they all over EV options…
Too much fanfare and too little real info shared to be of any value. Sounds more like an ad than infosec
Exactly what it is. A gross example of company trying to get their name out their by sensationalizing their findings.
Seriously wtf did I just try to read? It sounded like AI slop.
I’d like to know if this is just a firmware update or unfixable, but sadly this seems just an ad rather than news
Jews an article with a bit more detail… but I’m still unclear whether these backdoor commands are hardware circuits or firmware logic.
Bleeping Computer: Undocumented “backdoor” found in Bluetooth chip used by a billion devices
Solid article. I imagine the folks at the cyberwire podcast will be doing more digging over the weekend for a solid summary come Monday.
Thanks for the link, this article is more clear compared to the posted above.
I’m more interested to the scope of the exploit whether it could touch the flash of the controller or not as you can also do OTA update through the BLE component.
There is nothing to “fix”. Undocumented instructions have just been found in the silicon but they are not executable unless the ESP32’s firmware their owner flashed to give it a purpose uses them. No pre-2025 firmware that we know of uses these instructions, and they might turn out to be buggy so compilers might not adopt them. If they turn out OK, the documentation of the instruction set will need an update, and compilers will be able to take advantage of the new instructions.
It is not easy to determine how fixable this is. IIRC, the ESP32 has the wireless stack hidden from user space, and I am not sure if it is a blob included during link time, or if it is stored in a ROM of the chip. I do have the chips and the development enviroment in my studio, but (luckily) I decided to use a different chip for my project.
But I know there is a load of systems using either the ESP32 as their main processor, or as an auxiliary processor to add WiFi or BT capabilities, so this really is a big oh shit moment.
The Chinese adding back doors into their software/hardware.
Say it ain’t so!
Say it ain’t so
Your bug is a heartbleeder
Say it ain’t so
My NIC is a bytetaker
It ain’t so.
To use the “backdoor” an attacker needs to have full access to the esp32 powered device already.
It’s like claiming that being able to leave your desk without locking your PC is a backdoor in your OS.
Yes, this is about undocumented instructions found in the silicon but they are not executable unless the ESP32’s firmware uses them. Firmware cannot be edited to use them unless you have an existing vulnerability such as physical access or insecure OTA in existing firmware (as far as researchers know).
It is good to question the “backdoor” allegations - maybe the instructions’ microcode was buggy and they didn’t want to release it.
tech backdoors are only okay when us good guys require em
Where did anyone say anything remotely like that?
How about all tech backdoors are bad and we should aim to use and make software and hardware that is ethically produced and usable without selling out your privacy and security?
Like a PRISM for China, is every powerful country just backdooring each other?
Thats hot.
Not the first time a backdoor was found on Chinese made hardware and it won‘t be the last time. Decoupling can‘t happen quickly enough.
Which government’s backdoors would you prefer?
“We know you have a choice in oppressive governments, so we appreciate you choosing ours.”
None of them, that’s why the only things in my house that connect to the internet are my computers, game consoles, and cell phone
True, but the ESP32 is used by a lot of devices. This backdoor is pretty huge in scope of devices impacted.
It depends on what the method of attack is. I’m not seeing anything saying that it would be possible to exploit wirelessly, so this could easily be mostly a non-issue.
I mean, most users here are browsing using a device with an AMD or Intel CPU, both with known backdoors. Not the first time a backdoor was found on American made hardware and it won’t be the last.
One more reason to have actual open-source drivers instead of binary blobs…
I couldn’t find a list of devices. Anyone else find one?
Jokes on them, I live in America when all that shit was already done.
I read in another article that the identified 28 backdoor commands.
Is this some hardware flaw, or just something in their standard BT stack?
The ESP32 chip, developed by Espressif Systems, is widely used in various IoT (Internet of Things), embedded systems, and consumer electronics due to its low power consumption, built-in Wi-Fi & Bluetooth, and high processing capability.
Devices That Use the ESP32 Chip
ESP32 DevKit series (official Espressif boards)
M5Stack and M5Stick series
Adafruit HUZZAH32
SparkFun ESP32 Thing
LilyGO T-Series (T-Display, T-SIM, T-Watch, etc.)
WEMOS Lolin D32/D32 Pro
Sonoff Smart Switches and Plugs (e.g., Sonoff Mini R3, Sonoff S31)
Shelly Smart Relays (e.g., Shelly 1, Shelly 2.5)
Tuya-Based Smart Devices (many smart home products use Tuya firmware on ESP32)
Air quality monitors (e.g., AirGradient open-source air sensors)
IoT Sensor Hubs (various DIY and commercial solutions)
TTGO T-Watch (ESP32-based smartwatch)
Heltec WiFi Kit Series (LoRa-enabled IoT devices)
Fitness trackers (some DIY and prototype models)
ESP32-CAM (ESP32-based camera module)
DIY drones & robots (used in hobbyist and educational robotics)
3D Printer controllers (e.g., ESP32-based Klipper controllers)
ESP32-based vending machines (wireless payment systems)
Smart irrigation controllers
Energy monitoring devices (e.g., OpenEnergyMonitor)
Smart locks & security systems
ESP32-based web radios
DIY Bluetooth speakers
Smart light controllers with voice assistants
Why Is ESP32 Popular?
✔ Low-cost & powerful (dual-core, Wi-Fi, Bluetooth) ✔ Great for DIY & commercial IoT applications ✔ Strong developer community & open-source support ✔ Compatible with Arduino, MicroPython, ESP-IDF, etc.
Would you like recommendations for a specific type of ESP32-based device?
I have a bunch of ESP32’s that … I can update and replace the firmware on, if i reset it the right way with a usb cable. the web site doesn’t explain it any way how this is any worse than that…?
Yeah one of my more… tech adventurous friends had the most insane series of security breaches (to out it mildly) potentially related to this and some other recent ridiculousness.
Hey look china got caught putting backdoors in hardware AGAIN
So, what is the probability of it affecting a lot of people?
JcbAzPx@lemmy.world 1 hour ago
The rebuttal wasn’t as comforting as some are making it out to be. They seem to be more interested in the semantics of it not being a backdoor tied to a specific product, which appears to be true.
Rather it is a potential for vulnerability that exists in all wireless implementation, which seems to me to be a bigger issue.