 Research has found that UC Browser is insecure, with many vulnerabilities and privacy issues.In March 2019, analysts at the anti-malware firm Doctor Web publicly disclosed that UC Browser and UC Browser Mini for Android was downloading and installing extra modules from the company's own servers via an unprotected HTTP channel.This exposed browser users to arbitrary remote code execution if an attacker was able to perform a man-in-the-middle attack to deliver malicious module (but no cases of exploitation were publicly disclosed).