jsrsasign are vulnerable to Timing Attacks. The
signHex function uses a timing-unsafe method for ECDSA key generation and signing. This leaks the length of the scalar, which attackers may use to brute-force the private key. Timing attacks can be used to increase the efficiency of brute-force attacks by removing the exponential increase in entropy gained from longer secrets. This issue only affects the ECDSA functions.
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