Banks and regulators are warning against the rise of phishing scam involving QR codes.In a quishing scam, criminals send QR codes in PDFs attached to emails to bypass cybersecurity defenses.Victims often don't know where they are being directed until it's too late due to the visual difficulty of interpreting QR codes.The rise of quishing attacks adds to the increasing costs of cyberattacks, with phishing attacks costing businesses $4.9 million on average.