Description

A new wave of malware campaigns has emerged leveraging fake CAPTCHA verification pages to distribute LummaStealer, a well-known information-stealing malware. Instead of exploiting browser vulnerabilities, attackers are relying on social engineering tactics to trick users into executing malicious commands. The campaign marks a shift toward user-assisted infection methods, making detection more challenging for traditional security controls. The attack begins when victims are redirected to malicious or compromised websites displaying a fake CAPTCHA prompt. Unlike legitimate CAPTCHA systems, these pages instruct users to perform unusual actions such as copying and pasting commands into the Windows Run dialog or PowerShell terminal. Once executed, the command downloads and runs a malicious loader, often identified as CastleLoader. This loader operates primarily in memory, helping evade traditional antivirus detection. It then retrieves and deploys the LummaStealer payload from a remote command-and-control (C2) server. LummaStealer is designed to harvest sensitive data, including browser-stored credentials, session cookies, cryptocurrency wallet information, autofill data, and authentication tokens. Stolen data is exfiltrated back to attacker-controlled infrastructure, enabling account takeovers, financial fraud, and further network compromise. This campaign highlights a growing trend of “ClickFix” style attacks, where social engineering replaces technical exploitation as the primary infection vector.