Over 38,000 FreeDrain Subdomains Identified Engaging in SEO Exploitation for Crypto Wallet Seed Phrase Theft

Cybersecurity researchers have revealed an extensive global cryptocurrency phishing operation known as FreeDrain, which has been exploiting digital assets from cryptocurrency wallets over several years. The campaign has been identified by esteemed threat intelligence firms and represents a significant threat to users in the cryptocurrency space.

FreeDrain employs advanced techniques such as SEO manipulation, the use of free-tier web services (e.g., gitbook.io, webflow.io, and github.io), and complex redirection methods to lure victims. Researchers Kenneth Kinion, Sreekar Madabushi, and Tom Hegel have provided a detailed technical report outlining the operation’s methodology. Victims searching for wallet-related terms are directed to high-ranking malicious results, leading them to lure pages that redirection to phishing sites aimed at stealing their seed phrases.

The operation’s scale is notable, with over 38,000 unique FreeDrain sub-domains utilized to host lure pages. These pages are strategically hosted on major cloud services, mimicking the interfaces of legitimate cryptocurrency wallets, thereby enhancing their credibility.

Investigations suggest that the attackers operate from the Indian Standard Time (IST) zone during standard working hours, as indicated by activity patterns in GitHub repository commits linked to the lure pages. Notably, the campaign has been successful in targeting users searching for wallet-related queries, including phrases like “Trezor wallet balance,” and redirecting them to fraudulent landing pages.

Once users land on these deceptive pages, they are shown a static screenshot of what appears to be a legitimate wallet interface. This setup prompts one of three potential outcomes:
– Users are redirected to legitimate websites.
– Users are sent to intermediary sites.
– Users are directed to phishing pages that solicit their seed phrases, ultimately draining their wallet funds.

The researchers noted that this entire process is designed for maximum efficiency, combining SEO techniques, recognizable visual elements, and trusted platforms to create a convincing façade. Once a seed phrase is entered, the attackers’ automated systems can drain a victim’s wallet within minutes.

Additionally, the textual content of the lure pages might be generated using large language models, indicating how adversaries may exploit generative AI tools to create scalable phishing content. FreeDrain has also been seen engaging in spamdexing—flooding poorly-maintained websites with irrelevant comments to improve the SEO of their lure pages.

It is important to note that certain aspects of the FreeDrain campaign have been previously documented since 2022, indicating a persistent and evolving threat landscape. The reliance on free-tier platforms highlights the ongoing vulnerability of such services in the face of malicious abuses. Researchers concluded that FreeDrain serves as a modern model for scalable phishing campaigns, effectively evading traditional detection methods while adapting swiftly to any infrastructure disruptions.

This disclosure comes amid a growing concern regarding sophisticated phishing campaigns targeting cryptocurrency users. For instance, Check Point Research has identified another phishing scheme utilizing Discord to mislead crypto users into joining malicious servers, exploiting expired invite links, and leveraging the Discord OAuth2 authentication flow to avoid detection.

Between September 2024 and March 2025, it is estimated that over 30,000 unique wallets could have fallen victim to another phishing tool known as Inferno Drainer, resulting in losses exceeding $9 million. Although Inferno Drainer claimed to halt its operations, recent evidence reveals its ongoing activity, employing innovative anti-detection tactics including single-use smart contracts and encrypted configurations to evade wallet security measures.

The rising trend of malvertising campaigns further complicates the threat landscape, with attackers impersonating trusted platforms through targeted advertisements on social media that lead users to malicious sites. These deceptive tactics involve dynamic content delivery based on user behavior, enhancing the effectiveness of the attacks.

Overall, these cases underscore the necessity for users to exercise caution when navigating online cryptocurrency services and remain vigilant against potential phishing threats. As adversaries develop increasingly sophisticated methods to exploit vulnerabilities, continuous education and proactive security measures are paramount in safeguarding digital assets.