Collapse of data into unsafe value

// Normalising last can turn a character the check allowed into one it would have rejected.
class TitleSanitiser {
  def normaliseAfterChecking(supplied: CharSequence) = {
    // VULNERABLE: Collapse of data into unsafe value
    val forbidden = Pattern.compile("[<>]")
    val found = forbidden.matcher(supplied)
    if (found.find) throw new IllegalStateException
    Normalizer.normalize(supplied, Normalizer.Form.NFKC)
  }
}