[Cryptography] Other obvious issues being ignored?

[Thierry Moreau]

The recent realization that public key cryptosystems having common 
parameters (DH) may be vulnerable from the very fact that they rely on 
common parameters is puzzling to me.

In hindsight, the question would have been (highly) relevant ever since 
the practitioner had a choice between such cryptosystems and 
cryptosystems having entity-specific parameters (RSA, Rabin-Williams), 
the latter being vulnerable to flaws or trapdoors in the parameter 
generation implementation for each entity.

Moreover, the basic finding in the "Imperfect forward secrecy" 
publication (https://weakdh.org/imperfect-forward-secrecy-ccs15.pdf) was 
within the reach of skilled mathematicians ever since the number field 
sieve algorithm could be explained in a university classroom.

It's a shame that this old issue has been ignored until now!

What other "obvious" questions are we ignoring?

- Thierry Moreau