ZKP ⇒ Hash function

Statement

Migrated verbatim from zero-knowledge-proof § Other results:

ZK proofs for NP imply OWF in the plain model — standard

source: folklore: the claim carried no citation on the page it was migrated from, and none was invented.

class: unstated: no citing page says which notion of reduction is meant. Recording a class the wiki does not state would add a claim.

Recorded during migration and not fixed — these are claims about the source text, not changes to it:

FOLKLORE LABEL MISAPPLIED: this is an attributable theorem (Ostrovsky-Wigderson, OW93: non-trivial ZK implies one-way functions; also OW93/Ost91), not folklore. The CLAUDE.md folklore exception explicitly excludes results that have a canonical citation.
The precise statement needs ‘ZK proofs for a language outside BPP’ (or hard-on-average), not ‘ZK proofs for NP’ — and the conclusion in OW93 is one-way functions only under the auxiliary-input/average-case-hardness refinement. Reported as a precision concern.
Together with line 72 this asserts an equivalence OWF ⇐> ZK-for-NP that the page never states as such.
Conclusion node is again hash-function.md (the OWF/CRHF conflation).