SHORT SECURITY AUDIT REPORT
Shamir Secret Sharing Implementation
Bitaps JsBTC / PyBTC
A. Modulo 255 Defect (“Never 255 Bug”)
Polynomial coefficients never take the value 255 (0xFF) due to generator constraints (e.g., modulo 255 arithmetic or specific GF table usage).
Impact:
- The coefficient space is reduced from 256 to 255 possible values
- Entropy reduction is extremely small
Risk Assessment:
- Severity: Low
- Status: Non-fatal and does not reduce the Shamir threshold
B. Global Polynomial Coefficients (Static Across Bytes)
The polynomial coefficients (a₁, a₂, etc.) are generated once and reused across all bytes of the mnemonic entropy, instead of being regenerated independently per byte.
Impact:
- Secret bytes become correlated
- Polynomials are no longer independent per byte
- Shamir Secret Sharing security is significantly degraded
Status:
Design-level fatal flaw
My addres
18FXF47XcP52vhdbjimQ3CvD93NnHTPF73
SHORT SECURITY AUDIT REPORT
Shamir Secret Sharing Implementation
Bitaps JsBTC / PyBTC
A. Modulo 255 Defect (“Never 255 Bug”)
Polynomial coefficients never take the value 255 (0xFF) due to generator constraints (e.g., modulo 255 arithmetic or specific GF table usage).
Impact:
Risk Assessment:
B. Global Polynomial Coefficients (Static Across Bytes)
The polynomial coefficients (a₁, a₂, etc.) are generated once and reused across all bytes of the mnemonic entropy, instead of being regenerated independently per byte.
Impact:
Status:
Design-level fatal flaw
My addres
18FXF47XcP52vhdbjimQ3CvD93NnHTPF73