Widevine license acquisition failed with old widevinecdm.dll

[zhengheng36]

I am trying to get decrypt KEY and KID for a Udemy video.

I am using widevine-l3-decryptor. And I replace widevinecdm.dll with old widevinecdm.dll to fix the error: 'Can't verify license request signature; either the platform is wrong or the key has changed!'

After replacing the files, the video cannot be played and I found error from Chrome DevTool as below:


[Attachment 63014 - Click to enlarge]

Could anyone has the same problem after replacing with old widevinecdm.dll? could anyone help? Thanks in advance.

[lomero]

we have a lot of page/thread/post on this forum about this question ...
with old cdm you can't get the license request from the server, so he doesn't respond, so the video doesn't play ... simple.
need new working (latest) cdm to play video

[T33V33]

As lomero said there have been lots of posts about this already. Take some time to search first and you will have already had your answer.

To put it simply... widevine-l3-decryptor is broken... the old exploited widevinecdm.dll is revoked and cannot be used to obtain keys (or even play videos legitimately). The new widevinecdm.dll will allow playback of videos again but is not exploited so cannot be used to get keys

[zhengheng36]

we have a lot of page/thread/post on this forum about this question ...
with old cdm you can't get the license request from the server, so he doesn't respond, so the video doesn't play ... simple.
need new working (latest) cdm to play video

Thanks for the explanation lomero. The logic makes sense.

[zhengheng36]

As lomero said there have been lots of posts about this already. Take some time to search first and you will have already had your answer.

To put it simply... widevine-l3-decryptor is broken... the old exploited widevinecdm.dll is revoked and cannot be used to obtain keys (or even play videos legitimately). The new widevinecdm.dll will allow playback of videos again but is not exploited so cannot be used to get keys

Any working tools you recommend?

[cedric8528]

https://github.com/Puyodead1/udemy-downloader?ref=pythonrepo.com

[zhengheng36]

https://github.com/Puyodead1/udemy-downloader?ref=pythonrepo.com

I noticed this before. But cannot find a way to get the decrypted key...

[naim2007]

you need to patch widevinecdm.dll.
it's works fine with Udemy video.

[gtasanandreas5]

you need to patch widevinecdm.dll.
it's works fine with Udemy video.

how should we do that if you don't mind me asking?

[ancientbanana]

you need to patch widevinecdm.dll.
it's works fine with Udemy video.

Interested too, from what I saw, older version of cdm are revoked already and so if that's what you mean by patching, I am not sure if that would work, unfortunately.

[[ss]vegeta]

Interested too, from what I saw, older version of cdm are revoked already and so if that's what you mean by patching, I am not sure if that would work, unfortunately.

It no longer works.