I finally moved my fund from ledger wallet to software cold wallet and learned how to deal with cold wallet and transfer transactions partial signing online and then signing offline and broadcast it
Yeah, this doesn't sound right. Could you tell us a bit more about how you created your offline wallet, and what you did with the OS before you generated your keys on it? To make sure you are doing it properly, how are you signing those transactions?
why they don't tell us about cold wallet from begining instead of wasting our money on a fucking signing device
Is this a serious question? Do you expect a company that relies on the sale of hardware wallets to tell you not to use hardware wallets because you can get the job done with airgapped cold wallets? Even the marketing geniuses at Ledger wouldn't do that.
If you're referring to the firmware update that allowed the Recover "option" to work, it doesn't matter if you sign up for it or not; Ledger admitted they can pinch your private keys out of the secure element at any time, which they had previously said wasn't possible (and someone please correct me if I've got any of that wrong, but what I wrote is my understanding of what Ledger did and how it works).
They also claim that keys can't leave the SE enclosure without your permission, meaning physical confirmation on your hardware wallet with the button presses. I have no idea if that is true or not, and even if it is, there is no publicly verifiable code for them to back up their words. And finally, even if there is, I wouldn't know how to read it and can only hope that those who know take the time to study it properly. Basically, it's a carrousel of fuckery.
If I am not wrong, Ledger claims, "Here at Ledger we strongly believe in open source. It's one of our core values, a great philosophy that advocates openness, and verifiability. Open source allows developers and security experts to review the code and ensure it is secure and not malicious. Open source means you don't need to trust" [1]
Ledger Live is open-source and the crypto applications you install on your wallet are open-source. Some of them are created by third-party developers, some by Ledger in-house. The firmware and hardware isn't open source. You have no way of knowing what the software on your hardware wallet does.
Yeah....take a look at the links Findingnemo provided. This was but I do believe I read a post by a member whose knowledge I respect saying that in theory private keys could be extracted from any device with a secure element.
Using that same analogy, it would then be even easier to extract keys that aren't protected by a secure element chip. One example is Trezor's unfixable seed extraction vulnerability.
Ledger is not open source and it wasn't possible to know it was a lie that your seed phrase cannot leave the secure element, that was until they launched the Ledger recovery service, then their lies were exposed as well as many other flaws in the Ledger hardware wallet.
They exposed themselves. All everyone had to do was listen.