Widevine Upgrade using Pywidevine??

[helplesssalad]

A few months ago, I used KeyDive to extract Widevine L3 keys from my old RMX3261 (Realme C21y). This Worked well but with this Key everything I downloaded was only in 540p or 720p at max. But then I played around a bit with Pywidevine and found out that I could Export a Widevine Device (.wvd) file to an RSA Private Key and a Client Key and also Create a WVD file with these two files. I just tried it out and stumbled across the -l option that could define which widevine level to choose when creating a .wvd file from the Private Key and Client id. Just for fun i chose -l 1 and it actually worked. I got an L1 Widevine file. And I even could download the movies from amzn in FHD instead of SD which was very surprising to me. I mean I couldn't Download the Movies in 4k/UHD but its still way better than 540p.


I dont really know how Widevine works but I think this should be impossible because I didn't extract the l1 key from the TEE (I Wouldn't even know how to do that).
I guess it Isn't a real L1 CDM but AMZN handles it with more privileges.

I think many scammers could abuse this to sell worthless keys for hundreds of dollars and many wouldnt even realize

What do you guys think about this???

[larley]

Must've been a coincidence. Neither pywidevine nor WidevineProxy2 pay attention to the security level since it's only there for "documentation". The server decides what security level a private key has so it saves a request to a license server.

pywidevine: https://github.com/devine-dl/pywidevine/blob/master/pywidevine/cdm.py#L118
WidevineProxy2: https://github.com/DevLARLEY/WidevineProxy2/blob/main/src/library/isolated/util.js#L20