An issue was discovered in KaiOS 1.0, 2.5, and 2.5.12.5. The pre-installed Email application is vulnerable to HTML and JavaScript injection attacks. An attacker can send a specially crafted email to the victim that will inject HTML into the email application's UI as soon as the email is opened. At a bare minimum, this allows an attacker to take control over the Email application's UI (e.g., display a malicious prompt to the user asking them to re-enter their email credentials) and also allows an attacker to abuse any of the privileges available to the mobile application.