Does the issue of repeating the worth r nonetheless persist in the present day in Bitcoin transactions?
In case your query is whether or not Bitcoin signatures are nonetheless weak if their nonces are generated in a foul means: sure, completely. The safety of the ECDSA scheme (and the Schnorr scheme launched in BIP340) depends on signatures being created utilizing nonces which can be solely unpredictable to attackers.
Nevertheless, I do suppose it is honest to say that the software program stacks utilized in Bitcoin software program that constructs these signatures has matured so it happens much less in follow. Methods like deterministic nonces as standardized in RFC6979 makes it a lot simpler to jot down protected implementations.
If that’s the case, how can I discover transactions that comprise this factor?
There are questions on this web site that give extra sensible particulars, however in broad traces, you go over all of the blockchain’s transactions, group signatures by the general public key they’re created for, and inside every group see if any R worth is repeated. If that’s the case, you’ll be able to typically compute the personal key from the signatures.
I’ve analysis on the best way to defend digital belongings.
Use production-quality, well-reviewed, pockets software program or libraries. They are going to produce signatures in safe means. In case you’re writing code your self the place unhealthy nonces are a priority, you are virtually definitely doing one thing incorrect.
