The scam encourages recipients to scan a QR code and enter personal details.
If you receive such email, the HMRC advises not to engage and to report it to the HMRC phishing team by forwarding the email to [email protected].
While the HMRC uses QR codes in their official correspondence, they only do so to direct users to guidance. They will never ask you to submit personal information via a QR code.
The National Cyber Security Centre have guidance on the immediate steps you can take to protect your organisation against phishing attacks.
They also offer further specific advice on QR-enabled fraud in their recent blog: QR codes - what’s the real risk.