According to CoinMeta, the United States Internal Revenue Service (IRS) has issued a security warning about a sophisticated phishing attack targeting American cryptocurrency holders. Attackers forge official letters, posing as the IRS (using the guise of a "Digital Assets Compliance Portal" and claiming to be related to 1099-FORM filings), and attach QR codes to these letters. Once victims scan the QR codes with their phones, attackers attempt to steal their cryptocurrency wallet credentials and private keys.