Language: JavaScript
Label: vulnerable
CWE: CWE-347 \u2014 Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data.

Code:
function checkValue(b, q) {
  if (b.cmpn(0) <= 0) { throw new Error('invalid sig'); }
  if (b.cmp(q) >= q) { throw new Error('invalid sig'); }
}