CTM360: Lumma Stealer and Ninja Browser malware campaign abusing Google Groups Sponsored by CTM360 February 15, 2026 11:30 AM CTM360 reports that more than 4,000 malicious Google Groups and 3,500 Google-hosted URLs are being used in an active malware campaign targeting global organizations. The attackers abuse Google’s trusted ecosystem to distribute credential-stealing malware and establish persistent access on compromised devices. The activity is global, with attackers embedding organization names and industry-relevant keywords into posts to increase credibility and drive downloads. Read the full report here: https://www.ctm360.com/reports/ninja-browser-lumma-infostealer How the campaign works The attack chain begins with social engineering inside Google Groups. Threat actors infiltrate industry-related forums and post technical discussions that appear legitimate, covering topics such as network issues, authentication errors, or software configurations Within these threads, attackers embed download links disguised as: “Download {Organization_Name} for Windows 10” To evade detection, they use URL shorteners or Google-hosted redirectors via Docs and Drive. The redirector is designed to detect the victim’s operating system and deliver different payloads depending on whether the target is using Windows or Linux Windows Infection Flow: Lumma Info-Stealer For Windows users, the campaign delivers a password-protected compressed archive hosted on a malicious file-sharing infrastructure Oversized archive to evade detection The decompressed archive size is approximately 950MB, though the actual malicious payload is only around 33MB. CTM360 researchers found that the executable was padded with null bytes — a technique designed to exceed antivirus file-size scanning thresholds and disrupt static analysis engines. AutoIt-based reconstruction Once executed, the malware: Reassembles segmented binary files. Launches an AutoIt-compiled executable. Decrypts and executes a memory-resident payload. The behavior matches Lumma Stealer, a commercially sold infostealer frequently used in credential-harvesting campaigns Observed behavior includes: Browser credential exfiltration. Session cookie harvesting. Shell-based command execution. HTTP POST requests to C2 infrastructure (e.g., healgeni[.]live). Use of multipart/form-data POST requests to mask exfiltrated content. CTM360 identified multiple associated IP addresses and SHA-256 hashes linked to the Lumma-stealer payload. Explore CTM360’s HYIP Scam Intelligence Report. CTM360 identified thousands of fraudulent HYIP websites that mimic legitimate crypto and forex trading platforms and funnel victims into high-loss investment traps. Get insights into attacker infrastructure, fake compliance signals, and how these scams monetize through crypto wallets, cards, and payment gateways. Read the intelligence report here Linux Infection Flow: Trojanized “Ninja Browser” Linux users are redirected to download a trojanized Chromium-based browser branded as “Ninja Browser.” The software presents itself as a privacy-focused browser with built-in anonymity features. However, CTM360’s analysis reveals that it silently installs malicious extensions without user consent and implements hidden persistence mechanisms that enable future compromise by the threat actor. Malicious extension behavior A built-in extension named “NinjaBrowserMonetisation” was observed to: Track users via unique identifiers Inject scripts into web sessions Load remote content Manipulate browser tabs and cookies Store data externally The extension contains heavily obfuscated JavaScript using XOR and Base56-like encoding While not immediately activating all embedded domains, the infrastructure suggests future payload deployment capability. The installed extensions by the threat actor to the browser from server-side view Source: CTM360 Silent persistence mechanism CTM360 also identified scheduled tasks configured to: Poll attacker-controlled servers daily Silently install updates without user interaction Maintain long-term persistence Additionally, researchers observed that the browser defaults to a Russian-based search engine named “X-Finder” and redirects to another suspicious AI-themed search page The infrastructure appears tied to domains such as: ninja-browser[.]com nb-download[.]com nbdownload[.]space Campaign Infrastructure & Indicators of Compromise CTM360 linked the activity to infrastructure, including: IPs: 152.42.139[.]18 89.111.170[.]100 C2 domain: healgeni[.]live Multiple SHA-256 hashes and domains associated with credential harvesting and info-stealer distribution were identified and are available in the report. Risks to organizations Lumma Stealer risks: Credential and session token theft Account takeover Financial fraud Lateral movement in enterprise environments Ninja Browser risks: Silent credential harvesting Remote command execution Backdoor-like persistence Automatic malicious updates without user consent Because the campaign abuses Google-hosted services, the attack bypasses traditional trust-based filtering mechanisms and increases user confidence in malicious content. Defensive recommendations CTM360 advises organizations to: Inspect shortened URLs and Google Docs/Drive redirect chains. Block the IoCs at firewall and EDR levels. Educate users against downloading software from public forums/sources without verification. Monitor scheduled task creation on endpoints. Audit browser extension installations. The campaign highlights a broader trend: attackers are increasingly weaponizing trusted SaaS platforms as delivery infrastructure to evade detection. About the Research The findings were published in CTM360’s February 2026 threat intelligence report, “Ninja Browser & Lumma Infostealer Delivered via Weaponized Google Services” CTM360 continues to monitor this activity and track related infrastructure. Read the full report here: https://www.ctm360.com/reports/ninja-browser-lumma-infostealer Detect Cyber Threats 24/7 with CTM360 Monitor, analyze, and promptly mitigate risks across your external digital landscape with the CTM360. Join our Community Edition Sponsored and written by CTM360 .