ClaimsPrincipal.cs

private ClaimsPrincipal GetPrincipalFromToken(string token)
{
    var tokenHandler = new JwtSecurityTokenHandler();

    try
    {
        var principal = tokenHandler.ValidateToken(token, _tokenValidationParameters, out var validatedToken);
        if (!IsJwtWithValidSecurityAlgorithm(validatedToken))
        {
            return null;
        }

        return principal;
    }
    catch
    {
        return null;
    }
}

private bool IsJwtWithValidSecurityAlgorithm(SecurityToken validatedToken)
{
    return (validatedToken is JwtSecurityToken jwtSecurityToken) &&
           jwtSecurityToken.Header.Alg.Equals(SecurityAlgorithms.HmacSha256,
               StringComparison.InvariantCultureIgnoreCase);
}