Hacking a Knockoff Google Chromecast - Firmware Extraction

In this video, I extract the firmware from a Chinese Google Chromecast knockoff.
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[@Icemourne_]

14:47 At the bottom it says LZMA compressed data

[@4megii]

Glad I'm not the only one to see this. Rootfs is probably compressed within LZMA and then uncompressed and mounted via the bootloader.

[@RetroDelete]

I was just about to comment this, seems like it will be fairly easy to get access to the rootfs. +1

[@monad_tcp]

cliffhanger !

[@guiorgy]

Towards the end of the video I could swear I had seen "lzma" somewhere, went back to strings and watched closely while pausing, thought I was going crazy 😂

[@pete3897]

It's only 8MB though - the 980MB partition a couple above it will be the interesting one I would think...

[@Mr._Mythical]

I wish these videos were longer, i would love to sit here and listen for hours to you rambling about the innerworkings of a device nobody has ever heard of

[@doubled8511]

I love your videos man but they are just too damn short! I would happily sit here listening for a few hours whilst you ramble on figuring out how to extract the firmware.

[@kennwood]

Haha I was just thinking the same thing

[@M0UAW_IO83]

16:58, there's reference to SC16550UART so there's good possibility of a UART output somewhere on that board for the bootloader

[@bnister]

Yep indeed, it's pin 99 on the SoC muxed to UART2_TX quite early on. It's supposed to be pulled up externally + there are some suspicious test points at the other side, but, generally speaking, manufacturers rarely care enough to break this one out in any convenient way

[@qwertykeyboard5901]

Might be on the usb port. Sometimes they do that.

[@martontichi8611]

binwalker said on the bottom that there's LZMA compressed data. Uncompressed size is 7M! probably squashfs!

[@dazealex]

Also saw in the string something about unzip length.

[@dieSpinnt]

Great work and thanks for sharing, Matt:) Side-note, Tip, Womansplaining: Calipers 4TheWin! So you can measure the dimensions of the package. Works when soldered in and after some time you memorize the dimensions of TSSOP/SSOP/SOP/etc anyways. "To measure is to know!" And as a poor-(wo)men's-alternative: Print out a sheet with the whole zoo of electronics packages in the scale of 1:1

[@KallePihlajasaari]

Do you have a link to a sheet that you can link to for us other newbies?

[@unh0lyav3ng3r8]

@@KallePihlajasaari i got an actual ruler with different package sizes on it..

[@sjoervanderploeg4340]

@17:23 it clearly says HDCP :D "HDCP stands for High-bandwidth Digital Content Protection. The purpose of HDCP is to protect digital copyrighted content as it travels from a device to your TV, usually through an HDMI, DVI or DisplayPort connection." You might be able to interface that programmer with flashrom, I'm not sure if it is but it should be possible to implement! I own a "Willem EPROM Programmer", it also supports SPI flash memory like these but these days I generally use a very cheap ch341a_spi USB device.

[@tweebs1]

I really enjoy seeing how you methodically figure out how things tic and then bypass the security like its not even there. Firmware should be open, so we may use hardware as we see fit.

There's seem to be a compressed LZMA region, i'm pretty sure it's what you seen as high entropy, i'd bet it's the compressed rootfs mounted by the bootloader. Many times the MAC address is the one injected for the Wifi, as those modules don't have any hardcoded, Really interested to see your deep dive analysis. I'll join your discord, hopefully i can find the dump and analyze it myself also. I'd buy one of these if these if there's the possibility of a custom Firmware.

[@4megii]

I think you're spot on about LZMA being the rootfs and that it's uncompressed and then mounted by the bootloader.

[@allwitchesdance]

I bet it's going to be a kernel with the built in rootfs. No reason for these little gadgets to pivot root to a real file system

[@309electronics5]

​@@allwitchesdancei had a miracast device that had a full rootfs and a kernel. It even had a recovery kernel. Mine used a Actions semiconductor SOC

[@bnister]

Yeah a custom one is possible, but I bet you won't like the only FreeRTOS-based SDK available

[@Z-Ack]

I like how you spend way too much time going over all the laymen stuff like how to solder then jump through all the coding log processes and writing…lol

[@jamesdim]

My new favorite tech channel! Can't wait for the next hack adventure!

[@saschaschnuppe3409]

What exactly did he hack?

[@JerryThings]

I love this kind of videos where you showcase your adventure! Hope to see some in depth analysis in the future regarding the fw :D ty Matt

[@TheWarhoop]

Watching SMD's getting soldered onto PCB's is so satisfying... don't judge, I'm just saying what everyone's thinking. BTW, @Matt Brown, I switched to those little foam tipped eye makeup brushes which really elevated my flux clean up game over the Q tips, give 'em shot.

[@mattbrwn]

I'll have to try that. Getting those Qtip hairs everywhere is annoying

[@A_F_Innovate]

Thanks Matt for your great video. I love to see how you can pull these out and get the information from it.

[@rbmwiv]

Great video I just subscribed. I really enjoyed the one shot approach. Nice job. I am fixing to check out the second part!

[@ChrisMIA]

great stuff bro! been so much into software have been slacking on the hardware firmware side of things, good to have this under my belt especially with todays supply chain being chip tainted

[@wasabinow]

Cool stuff! Thank you for sharing your electronic adventures!

[@adamkavala]

Good job, looking foward to see more progress.

[@saad1983]

@Matt Brown good sir. you are on fire lately. another awesome video.

[@samuraidriver4x4]

The silkscreen of footprint on the board is a bit akward due to it being a fairly universal footprint. I do agree with you about the lead free solder, its definitely leaded solder seeing how easy it melted. No issues with using leaded solder in in China.

[@n2cthe1]

love your videos, i also think there too short... i enjoy complete and in-depth look into IoT

[@paerrin1]

Another great video! Keep them coming!

[@UndeadAlex]

Loved this man awesome work!

[@tal1296]

Love your videos,I saw in strings HDCP which is hdmi copyright protection

[@aldythsatya601]

Glad to see this video, I don't understand the KZbin algorithm but videos like this don't show up when I search for them, but they magically appear on the homepage 🗿. And I have 4 devices like that that can't connect even though they have been reset

[@fronbasal]

Matt this was absolutely fantastic. Thanks for sharing!

[@pamelax64]

Let's wait for the next video about it,interested!

[@richiebricker]

very cool stuff. I look forward to learning from ya

[@antivaxxtoaster8919]

Another banger as per usual

[@Fatpumpumlovah2]

Really? What did you learn? Nothing but more propraganda, every device you own is made by chinese/taiwanese companies. America makes nothing and tbis guy has no clue

[@functiontek]

Don't know if someone already mentioned it, but I would bet that key you saw mentioned at the start is unrelated to the encryption. It has "HDCP" in it, which would make more sense to be HDMI Content Protection instead.

[@meowyahh]

Really good work, youtube's algorithm brought me here!

[@mikehensley78]

same. a few weeks ago a Matt Brown video was in my recommended vids. i been subbed/watching ever since.

[@mmkf]

I wonder if the filesystem is compressed in a non-standard way.

[@pap3rw8]

I would guess it's compressed based on the output of strings including "unzip" but it's possible there's also some encryption of the bootloader or whatever.

[@davidezequielborges392]

to clean stuff you can use an old toothbrush instead of qtips so it doesnt left off any fibers, at least to remove the most of flux witout much hussle.

[@qweriop]

Thank you youtube for showing me this channel! I love this kind of electronics hacking!

[@user-wy6iy7ij1z]

It is like reading and flashing a motherboard BIOS chip, I did it many times, but after this, I didn't understand anything anymore, but this is really cool.

[@raraujo4951]

Great video Matt,!!!

[@revancedsubsfuckgimp]

Great video! Instructions (sequences of 4 bytes that end with a 0x3x byte) kinda remind me of little endian MIPS (similar to how ARM instructions can be identified by the 0xEx bytes)

[@riccardopolelli1825]

Cannot wait for part two

[@jheimissantos8682]

Nice video, Matt! Tks for share your knowledge! It's possible extracting the firmware via software? connecting via terminal (adb) and copy some partitions? sometimes i have dificult to consider what is the firmware, e.g all image firmware or only bootloader firmware.

[@309electronics5]

Adb is android only. If a device runs Uboot as bootloader you can interrupt the boot process and dump the flash.

[@bnister]

@@309electronics5 This one doesn't, everything is proprietary. Doesn't like to respond over USB, as well. There's usually some form of OTA on these, though, but dumping is tough

[@Sonny482]

Great job! Which microscope / camera do you use?

[@surewill8190]

always interesting to watch

[@arashgudarzi2623]

hey Matt, I like you videos and watched many of them. I am a student who loves hardware hacking. I started electronics basics and Arduino to kinda get familiar with the hardware stuff. do you have any roadmaps to be successful in this field of job ?

[@matheuscezar6309]

Nice! I'm curious to discover how to decompress/decrypt those data!

[@bnister]

Bog standard LZMA. binwalk -e handles it well, but any unlzma tool will suffice. An RTOS2 SDK seems to come with the unmodified LZMA build from Igor Pavlov, too

[@videshx818]

Nice soldering skills, I have one of this device in which the micro USB is detached. I am yet to solder

[@samuie2]

There were multiple strings that referred LZMA and unzip "main code". I think that the code is just compressed, and the key if for hdmi drm not the firmware.

[@tomu1337]

Another great video!

[@adagioleopard6415]

They put two footprints on top of one another so if the wide version of the chip is unavailable they can use a regular soic8. We did the same but we at least made a package with nice looking silk so it didn't look so crap

[@bnister]

You've got a fairly standard ALi Tech sat receiver dump :-) These run off a proprietary TDS2 RTOS. The HCSEMI clone chips have a FreeRTOS SDK available, but it's not as stable tbh

[@revancedsubsfuckgimp]

And here I was wondering why the NCRC string seemed so familiar.... likely MIPS based as well

[@wlloxik]

this is the perfect video to listen to in the background lmao

[@Ibrahim-rc8sn]

What analyzation software do you use in 18:50 ? I subscribed to your channel , great content

[@ilyassamraoui3234]

That's binwalk program running -E [capital e for Entropy, if -e it will extract firmware "structure" I guess ]....

[@mikesyr]

Hi Matt, do they make clips for SOP8s that size? Seems like that would be quicker than desoldering that chip, then again it came off with no issue. :)

[@309electronics5]

Sadly often when you put the clip on it powers the flash but also the soc/cpu its connected to which then tries to read from it and messes up the firmware read

[@bnister]

Yeah this exact platform has no trouble being dumped via the cheap ass clip usually shipped with CH341A kit. The LZMA packed firmware gets extracted to the RAM, and the SPI chip gets almost no accesses at all

[@adnanalam6201]

Dude I've the same thing 😅 gotta follow this guy now

[@quetzalcoatl-pl]

16:20 'anonymous' and '88888888' sounds like a default user-password pair, 8x 8 being the password, IIRC the '8' is a lucky number in china, so eight 8x would be sth like seven 7s in US.

[@TerrisLeonis]

"anonymous" as the username makes me think of FTP.

[@poweron3654]

17:18, NCRCHDCPKey refers to HDCP, or high-bandwidth digital content protection, it is not an encryption key for the firmware

[@AymanAlhkeemi]

Please make a video on how to rebuild the firmware and calculate the checksum

[@Roadbobek]

I have no idea what’s going on but I watched the whole thing

[@-r-495]

using possibly compromised sw to dump a knockoff product. like it! 😏

[@ratkaelzey]

kay, I’ve always scratched my head about the obsession around the kislux book totes and their practicality, but this one is adorable!! Congratulations

[@MotSter]

does it not work out of the box? Is there a further use goal to add to it or is this just pull the firmware cause you can as title kind of obviously states?

[@user-vg4io9sl9g]

The problem of Chromecast devices is too small internal storage, and i am curious can you replace the original with a bigger one?

[@CosmicMyst]

I think I ventured into the fun side of KZbin

[@duefourbail]

what terminal ui is that when you check through the device i’m trying to learn more about the software you use

[@skeffers1988]

I have tryed to hack the m5 displays / ebike controller . I cant get the firmware extracted from this device over uart . I have 2 uart connections on this board this m5 display comes with the nuvoton MS51FCOAE whitch has more uart connections on it .

[@pachapa3030]

This is awesome

[@user-ff5yb9hh6c]

I used bug prove for complication software.İt's can't decyrpt firmware if it's encyrpted but if it's uncrypted bugprove can good job and you can detect old binarys,vulnarabilities etc.

[@MrCustomabstract]

Goated vids

[@Its2Reel4U]

Love it

[@kikihun9726]

It had a hdcp string above so that encrypted data propably contains hdmi hdcp handshake key too.

[@allwitchesdance]

The two lzma blobs are probably the kernel and initramfs

[@bnister]

One's the kernel, and another (usually) the localization data. This thingie doesn't need any fs at all

[@roelbrook7559]

You've got LZMA compressed data there. That might explain the entropy results you're seeing.

[@nohaynoticias]

"the logo for the company that makes this device" SHERLOCK!

[@Neolith100]

If the XGecu Pro software is windows, how do you run it in linux? Are you using WINE or Bottles... I am incredibly curious?

[@mattbrwn]

Wine

[@hafiz468]

8:16 What the FLUX is going on here ?! 😂

[@rrrlasse2]

I think if it's encrypted, entropy is almost exactly 1. If it's compressed it might be slightly lower

[@toxicpsion]

that entropy spike is totally compression; probably a ramfs of some kind, looks like it showed up at the bottom of binwalk.

[@phuo2185]

can you make a video on synology TC500

[@reddinghiphop1]

Fantastic

[@gatitomono47f77]

Hello I wonder I've seen that theres also clips for Ic's like the one you desoldered like would It have been easier to Connect with a clip to the reader or am I missing slmething

[@mattbrwn]

I have clips to do that but I prefer to take the chip off

[@Ibrahim-rc8sn]

Where can I find this software you use called Xgpro in 5:00 ?

[@UndernetSystems]

The good thing about dumping the firmware is that you can just buy another flash chip and reflash it if it breaks.

[@bnister]

Not unless the firmware ties itself to the flash Unique ID, and Chinese-sourced thingies usually DO... as a form of copycat protection

[@andreamitchell4758]

Can you extract FW from a twinkly ARGB LED controller next

[@jonathanzimmer8143]

Great video this was fun! Please do something on a Vortex phone, Oxtab tablet or other freeware. TV devices are big duh, I have an M-95 4k box that was immediate full throttle/unresponsive... turns out they're pretty much all spyware. Tried to hack my google acct from Shenzen. Oops. But devices handed out to the elderly etc are no longer motorola or lg, but chinese companies with knock off Galaxy designs and questionable Android builds.

[@Cotten-]

What's up bro. I have a LG Stylo 6 that I'm trying to unlock the bootloader on. I can't get mtk client to recognize the device and I learned that someone else got theirs to become recognized by taking apart the phone and using a jumper wire on the board. Do you think that you could just Google a picture of the board and tell me which pins the jumper wire needs to touch for this process. If I blow my device up then I know that that's my problem. I trust your expertise which is why I'm asking you. Thanks for the videos either way I really appreciate them.

[@frtls]

Are these not cracking videos?

[@gamerriasaat6622]

How about modding a xiaomi 4c router (which is really cheap) to port usb(it has two open data pins) and openwrt (just enable ohci and ehci in kernel while complling) and then make a wifi pineapple(decompile pineapple rom and port using overlay) bcz they both use mips24kc :) then tada 15$ pineapple 🍍 btw it has better specs then original pineapple...

[@gamerriasaat6622]

I can't try this bcz of my upcoming entrance exam for varsity...

[@Holycurative9610]

The anycast logo looks like it was stolen from Paul Daniels of Apple fixing fame...

[@VSteam81]

Just curious, what linux distro and DE/WM do you use?

[@mattbrwn]

Arch Linux and i3wm

[@VSteam81]

@@mattbrwn Holy shit that was fast. Nice! I've used i3 and its really cool to have something that is so configurable.

[@foufou33g]

the key thinh seems HDCP related ?

[@md.arifulislamarif8077]

sir Is it possible to read the program of IC provided by pic Microcontroller? Protected ic

[@KallePihlajasaari]

Only if you are very dedicated and some security vulnerability has been discovered. Many times those offering such read out services do not share the vulnerabilities so you may have to spend time looking to find the operation that has the skills to defeat the security on your specific chip. Generally the older the chip the more likely it is that a security bypass exists.

[@KnexJunkie]

I have specifik problem with Samsung A53 budget smartphone -- they have nice software to mirror cast towards smarter monitors sadly i got a special ROG 17 inch portable monitor with a battery in it with a stand that doesnt have this. / Also the casting devices mostly use a external power supply to be connected to a power port. + ather thing this monitor use a HDMI mini camera port in it also has USB c to usb c display support (sadly most newer phones dropped support for this). I was wondering how to make a ANYCAST or ather casting device into a portable configuration. I do know how to solve the HMDI thing with adapter probaly from big to mini + i dont know if theres a way to connect bluetooth to a cast device to use the Wifi from the phone for Netflix. --- Anyways i wonder if might be cheaper for me to look for ather phone then to build something to fix this problem XD --- it could be im confused somewhere in my thought process about casting devices but i sadly cant do Usb c to usb c display with this phone i own at the moment. because that would have save me a lot of hassle.

[@kairu_b]

Interesting

[@VulcanOnWheels]

1:01 You say, "*to* your TV", but I read "*on* your TV". Why do you keep hitting the Return key so often?

[@hoteny]

Now you are an agent huh

[@AppliedCryogenics]

Even if it's just video playback + TCP/IP stack + some RTOS, 4MB compressed seems wayyy too small to be the whole firmware.

[@hafo821]

it´s not a SPY flash it´s SPI flash! 🤣😁

[@mattbrwn]

I also say Sequel instead of SQL... 😂

[@mikehensley78]

A day off work and hacking a cloned chromecast with MattyB! what else could ya ask for??

[@georgeyreynolds]

A lot of these devices have malware on them which lies dormant. If it turns out to be android etc , mainly the Android TV types.

[@309electronics5]

I actually had an miracast device which looked and worked simmilar to this. Just that it had an actions semiconductor soc and had 2 uarts onboard and i got a shell. Its funny to me how these chinese manufacturers manage to put Linux on everything (Shows how great Linux really is) but wont comply (at least my device type) with the GPL. Sadly yours might be running some custom os or a RTOS. Or its a weirdly formatted Unix os but thats unlikely. It might be encrypted and that the bootloader decrypts it and mounts the os

[@bnister]

Nooope no Linux this time around, with no way to run one, to boot

[@MrL22]

14:46 LZMA compressed block hinting at 7.8mb of uncompressed data.