While using file upload function the security scan is showing high risk. The code as show below,

<input type="file" accept=".csv" (change)="uploadfile($event)">

uploadfile(e) {
    const reader = new FileReader();
    reader.onload = () => {
      const data = reader.result;
      this.performcalc(data);          
    };
    reader.readAsBinaryString(e.target.files);
  }

while the above code scan, it show high risk. In between have done validation and sanitize, but still showing high risk.

Is there any better solution to avoid security risk.