Generally
I don’t think we can come up with a definite “keep” or “kill” to this meta Q as we’ve all seen that a “good question” can make very much sense and show imense quality, even when the topic itself is regarded to be – let’s just call it – a bit critical. (eg: some might remember all those Snowden Q&As, several RSA-breaking Q&As, etc.).
In the end, I would say it always depends “what they ask” and “how they ask”, and “what they explain” (eg: showing research efforts, what exactly they‘re not grasping etc.) If an asker manages to clearly express his/her Q, I’m all-in for keeping it around.
But when an asker reboots things using different wording while asking what was asked and answered before… well, that’s where the fine line resides that helps decide if it’s a dupe, or not. When such a rebooted question doesn‘t even add anything to it, which might help differ and/or clarify the difference between the two,there’s not much else we can do besides asking forsuch additional information and/or a clarification via a comment and hope for the best.
In relation to the Q discussed here
When I first looked at that question, I could’t help noticing the Q’s initial problem of being rather broad:
What are the characteristics of different algorithms that could be used in such a hacker scenario?
I mean, where should we start when trying to answer that Q in a few paragraphs?
Untill the asker clarifies his/her research efforts, his/her knowledge level, etc. (as I‘ve requested via my comment) we don’t know if the asker already did any research related to crypto algos and/or ransomware that uses it. We certaily can’t see from the question what kind of crypto-knowledge level the asked might or might not have.
In a worst-case scenario, we might be forced to begin from scratch with an general introduction to cryptography, then explain a yet-to-be-defined amount of ciphers et all, followed by explaining public cryptography from A-Z, how different forms of cryptanalysis and attacks work, and who-knows-what beyond that. And we still would’t have mentioned the word ransomware yet – which merely uses cryptographic means to achieve it’s illegal purpose which frequently causes negative security impacts on individual victims or groups of victims.
Ignoring worst-cases
Even when completely ignoring the described broadness issue for the benefit of the doubt, I end up noticing that today’s ransomware Q hardly asks anything that wasn’t already asked before. To me, it almost reads like a rephrased duplicate (with an additional “broadness problem”).
To be exact, I think today’s ransomware Q might already find a perfect answer at this likewise generalized, yet less broadly formulated Q&A:
“Understanding ransomware – What makes plain-text-attacks or brute-forcing so hard?”
That one was asked and answered in back in January 2016. It’s not yet clear to me what today‘s Q might be asking beyond that. I’m still waiting for the requested clarifications by today’s ransomware-question poster.
Going Canonical
Should the community decide we indeed need a caninocal, ransomware-related Q, I would support that decision to the fullest while suggesting we build upon what we already have.
After all, Otus’ answer from back in January 2016 already provides a perfect base which we could build upon by adding additional information via answers (whenever that makes sense).