this post was submitted on 08 Mar 2025

902 points (93.7% liked)

Technology

64937 readers

4040 users here now

This is a most excellent place for technology news and articles.

Our Rules

Follow the lemmy.world rules.
Only tech related content.
Be excellent to each other!
Mod approved content bots can post up to 10 articles per day.
Threads asking for personal tech support may be deleted.
Politics threads may be removed.
No memes allowed as posts, OK to post as comments.
Only approved bots from the list below, to ask if your bot can be added please contact us.
Check for duplicates before posting, duplicates may be removed
Accounts 7 days and younger will have their posts automatically removed.

Approved Bots

founded 2 years ago

MODERATORS

L3s@lemmy.world

enu@lemmy.world

technopagan@lemmy.world

L4s@lemmy.world

902

Undocumented Commands Found In Bluetooth Chip Manufactured in China Used By a Billion Devices. (www.tarlogic.com)

submitted 1 day ago* (last edited 6 hours ago) by Tea@programming.dev to c/technology@lemmy.world

169 comments fedilink hide all child comments

Source Link Privacy.

https://themarkup.org/blacklight?url=https%3A%2F%2Fwww.tarlogic.com%2Fnews%2Fbackdoor-esp32-chip-infect-ot-devices%2F&device=mobile&location=us-ca&force=false

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.

Update: The ESP32 "backdoor" that wasn't.

(page 2) 50 comments

sorted by: hot top controversial new old

[–] ycnz@lemmy.nz 104 points 18 hours ago

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.

[–] notanapple@lemm.ee 139 points 21 hours ago (6 children)

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.

[–] secret300@lemmy.sdf.org 23 points 15 hours ago (2 children)

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.

[–] ChaoticNeutralCzech@feddit.org 2 points 9 hours ago

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).

load more comments (1 replies)

[–] rottingleaf@lemmy.world 7 points 13 hours ago

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.

[–] unemployedclaquer@sopuli.xyz 11 points 19 hours ago

Yeah tons of weird little private softwares never get updates, but they aren't making anyone money either

load more comments (3 replies)

[–] Ebby@lemmy.ssba.com 199 points 1 day ago (1 children)

Well... Shit.

There are so, so, so, many ESP32's in not just my house, but practically everyone I know.

There outta be fines for this BS.

[–] cogman@lemmy.world 153 points 1 day ago (18 children)

You're fine. This isn't something that can be exploited over wifi. You literally need physical access to the device to exploit it as it's commands over USB that allow flashing the chip.

This is a security firm making everything sound scary because they want you to buy their testing device.

[–] Blue_Morpho@lemmy.world 67 points 23 hours ago (3 children)

You literally need physical access to the device to exploit it

You don't need physical access. Read the article. The researcher used physical USB to discover that the Bluetooth firmware has backdoors. It doesn't require physical access to exploit.

It's Bluetooth that's vulnerable.

https://www.bleepingcomputer.com/news/security/undocumented-backdoor-found-in-bluetooth-chip-used-by-a-billion-devices/

[–] ChaoticNeutralCzech@feddit.org 2 points 9 hours ago

[–] cogman@lemmy.world 69 points 22 hours ago (1 children)

I just re-read the article and yes, you still need physical access.

The exploit is one that bypasses OS protections to writing to the firmware. In otherwords, you need to get the device to run a malicious piece of code or exploit a vulnerability in already running code that also interacts with the bluetooth stack.

The exploit, explicitly, is not one that can be carried out with a drive-by Bluetooth connection. You also need faulty software running on the device.

[–] Blue_Morpho@lemmy.world 18 points 21 hours ago (1 children)

"Depending on how Bluetooth stacks handle HCI commands on the device, remote exploitation of the backdoor might be possible via malicious firmware or rogue Bluetooth connections."

I of course don't know details but I'm basing my post on that sentence. "Backdoor may be possible via ... rogue Bluetooth connections."

[–] haleywm@startrek.website 71 points 20 hours ago (2 children)

Looking at the article, the exploit requires you to be able to send arbitrary data to the Bluetooth device over a physical connection. This means that a properly secure application will be protected from drive by connections, but if the application has an exploit that either lets an attacker write arbitrary values to the Bluetooth controller, or more likely contains a general arbitrary code execution exploit, then you could use this to rewrite values to the chip that would let you "persist" certain changes to the Bluetooth chip that would be difficult to notice.

I would consider this a moderate concern, as this will definitely increase your options if you're looking to be able to make an attack that targets a specific device and this gives you a few additional persistence options, but any attack would have to be designed for a particular program running connected to a Bluetooth chip.

A more likely concern in my opinion would be the possibility of a supply chain attack, where someone compromises a Bluetooth chip that they know will be used to construct a particular part.

I don't think that it's super likely that either of these will affect the average person, only corporations and governments where espionage is an actual threat, as if you can find a Bluetooth IOT device that you want to mess with, like a Bluetooth enabled door lock, then you're more likely to be able to find an arbitrary code execution attack which causes it to unlock immediately. Being able to spoof a different Bluetooth device isn't likely to give you that big of an advantage when you're working with a device that was already vulnerable for a different reason.

[–] ByteJunk@lemmy.world 2 points 13 hours ago (1 children)

Thank you for the analysis, very insightful!

Do you reckon this is more of an oversight or bug in the BT stack, or a deliberately places backdoor as the title seems to suggest?

[–] haleywm@startrek.website 6 points 11 hours ago

From what I can tell from looking at it, this seems like something deliberately left in, but not for malicious reasons. The op codes referenced simply give access to lower level parts of the boards programming. ESP32's are already a user programmable board, a valid use case is to run your entire application on one if the code being run is lightweight enough to not interfere with the Bluetooth code. Either during development, or during runtime, these undocumented codes are likely used to run specific commands on the board.

The actual issue as far as I can tell, since normally it's valid usage to rewrite the board over USB, is that ESP32 boards also offer ways to encrypt device code, and require it to be signed, and you are presumably able to mess with this in order to dump code that was expected to be securely encrypted, and overwrite code on devices that was intended to require signing. (https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/security/secure-boot-v2.html#background)

Proving what someone was thinking when they programmed something is extremely difficult unless you can find written evidence of someone specifically saying if they did something or not, but this all seems like a legitimate minor exploit in a device that wasn't built by, or intended for, people who are working against highly resourced attackers. This is still not a concern for normal people who aren't concerned about being attacked by spies, and if a nation state wanted to hide a vulnerability in something then there are far easier paths to take than one that only works if you can steal a microcontroller so you can connect to it over USB.

load more comments (1 replies)

[–] IllNess@infosec.pub 30 points 22 hours ago

Depending on how Bluetooth stacks handle HCI commands on the device, remote exploitation of the backdoor might be possible via malicious firmware or rogue Bluetooth connections.

I really wish these articles just tell us what these scenarios are. I understand companies need publicity or need to sell software but if it isn't replicatable and the article says "might be possible" it kind of sounds like a secuity sales pitch.

This is especially the case if an attacker already has root access, planted malware, or pushed a malicious update on the device that opens up low-level access.

This part basically sounds more like a software issue where the attacker has a way in already. The system is already vulernable at this point before using the exploit found.

I don't think there's enough information out yet.

It is very interesting though.

load more comments (17 replies)

[–] NightCrawlerProMax@lemmy.world 44 points 20 hours ago (13 children)

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.

[–] matlag@sh.itjust.works 27 points 17 hours ago (2 children)

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.

[–] themurphy@lemmy.ml 12 points 15 hours ago (1 children)

Europe and its 50 car makers could also be considered instead of China..

load more comments (1 replies)

[–] NightCrawlerProMax@lemmy.world 7 points 14 hours ago (5 children)

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.

load more comments (5 replies)

[–] Montreal_Metro@lemmy.ca 10 points 17 hours ago* (last edited 17 hours ago) (2 children)

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. If I was fighting a cold war, I would do the same. Sell compromised devices to my trade partners (AKA enemies) so I have leverage when I need it.

load more comments (2 replies)

load more comments (11 replies)

[–] Oisteink 82 points 23 hours ago (2 children)

Too much fanfare and too little real info shared to be of any value. Sounds more like an ad than infosec

[–] qqq@lemmy.world 5 points 15 hours ago

Seriously wtf did I just try to read? It sounded like AI slop.

load more comments (1 replies)

[–] mechoman444@lemmy.world 24 points 21 hours ago (12 children)

The Chinese adding back doors into their software/hardware.

Say it ain't so!

[–] Dekkia@this.doesnotcut.it 8 points 13 hours ago (1 children)

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.

[–] ChaoticNeutralCzech@feddit.org 2 points 8 hours ago

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.

[–] NaibofTabr@infosec.pub 22 points 21 hours ago

Say it ain't so
Your bug is a heartbleeder
Say it ain't so
My NIC is a bytetaker

load more comments (10 replies)

[–] RmDebArc_5@sh.itjust.works 43 points 1 day ago (7 children)

I’d like to know if this is just a firmware update or unfixable, but sadly this seems just an ad rather than news

load more comments (7 replies)

load more comments