Why does a missing constraint in my ZK circuit survive five separate audits?
Szansa
ZK circuits can contain constraints that are syntactically valid but logically incomplete, leaving the witness underconstrained so an attacker can construct a fake proof the verifier accepts. The Zcash Orchard circuit had exactly this bug, disclosed in June 2026 after sitting undetected for four years through multiple professional audits. Existing static analysis tools catch simple cases but cannot prove completeness over a full production circuit. Fuzzing finds individual bugs but generates no soundness guarantee. No workflow in standard use today can tell you, before deployment, that your circuit has no underconstrained witness.
Dlaczego to ważne
A single missing constraint is enough to let an attacker mint value from nothing, and no standard pre-deployment workflow gives a completeness guarantee over a full production circuit.
Jak oceniam szansę
Wskaźnik Szansy to mój własny odczyt, a nie pomiar: jak bardzo boli, jak często daje się we znaki i jak niewiele istnieje dziś, by to rozwiązać. Wyższy wynik oznacza, że uważam problem za bardziej warty zbudowania.
Ile bólu sprawia, gdy się pojawia.
Jak często ludzie faktycznie na to trafiają.
Jak mało dobrych narzędzi istnieje dla tego dziś.
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