Opera Mini for Android below 53.1 displays URL left-aligned in the address field. This allows a malicious attacker to craft a URL with a long domain name, e.g. www.safe.opera.com.attacker.com. With the URL being left-aligned, the user will only see the front part (e.g. www.safe.opera.com…) The exact amount depends on the phone screen size but the attacker can craft a number of different domains and target different phones. Starting with version 53.1 Opera Mini displays long URLs with the top-level domain label aligned to the right of the address field which mitigates the issue.

The Opera Mobile application before 12.1 and Opera Mini application before 7.5 for Android do not properly implement the WebView class, which allows attackers to obtain sensitive information via a crafted application.