Hackers stole software-signing certificate from Opera and used it to write malicious code. Thousands of Windows users were infected with password-stealing malware. Opera advised users to run a browser upgrade as soon as it becomes available. No personal data has been compromised, according to the Oslo-based company. The company is working with authorities to investigate the source of the cyber-attack and any potential extent of the breach. More than half of the antivirus solutions detected the malware at the time of writing.”]