Unsafe validation RegEx in EmailField component in com.vaadin:vaadin-text-field-flow versions 2.0.4 through 2.3.2 (Vaadin 14.0.6 through 14.4.3), and 3.0.0 through 4.0.2 (Vaadin 15.0.0 through 17.0.10) allows attackers to cause uncontrolled resource consumption by submitting malicious email addresses.