I am not a robot: ClickFix used to deploy StealC and Qilin 19:15 - 18 Dec 2025 news.sophos.com The fake human verification process led to infostealer and ransomware infections https://news.sophos.com/en-us/2025/12/18/i-am-not-a-robot-clickfix-used-to-deploy-stealc-and-qilin/