Note from Lionel: Welcome to the third post in our Future Insights 2025 series. This post from the X-Labs research team analyzes the rise of malware campaigns built on top of legitimate infrastructure services. Click to read previous posts in the series.

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Throughout 2024, as we continued tracking activity around the latest malware and phishing campaigns, the X-Labs team noticed a trend: hackers are moving away from using compromised websites for hosting malware to building malware campaigns on legitimate infrastructure services. Based on our data, we expect that trend to accelerate into 2025 and beyond.

Malware Campaign Examples

Take blogspot.com, Google’s free domain service that provides a subdomain for Blogger. That’s where we found Agent Tesla malware authors hosting stage payloads there. In July, we saw a rash of activity emanating where hackers leveraged Trycloudflare.com and Python to deploy AsyncRAT malware. And the Remcos RAT activity we blogged about in June also leveraged Trycloudflare.com. Hackers used TryCloudflare for XWorm and other malware campaigns as well. The Snakekeylogger malware campaign used Discord CDN as a public content distribution network to host malicious files.

Hackers leveraged Secureserver.net heavily for malware activities as well. That was the origin of a malware campaign we blogged about that primarily targeted financial institutions in Latin America. Additional malware like Grandoreiro and the NetSupport RAT leveraged Secureserver.net domain as well. To provide a sense of scale, Forcepoint intercepted over 3.7 million suspicious emails that contained Secureserver.net URLs just in the last few months:

In the case of Remcos and Agent Tesla, we found examples of both using free services to host steganography images or other stage downloads:

uploaddeimagens.com.br
archive.org
raw.githubusercontent.com

For data exfiltration and command and control communication, several malware campaigns leveraged the following legitimate services:

ONE - Dynamic DNS Services
Hackers use these services to change IP addresses in an effort to evade detection.

freeddns.noip.com (servequake.com)
freeddns.dynu.com
duckdns.org

TWO - Telegram Bot API
The Telegram Bot API allows bad actors to build bots to interact with users on the Telegram platform.

api.telegram.org/bot

THREE - Small File Hosting Services

Storing files using well-known free storage services makes it more difficult to track malicious activity.

qu.ax
store2.gofile.io/download

FOUR - Port forwarding services:

Storing files in multiple well-known remote locations makes it more difficult to track ongoing malicious activity.

ply.gg
portmap.host

To get a sense of scale on the hackers switching to legitimate services, we analyzed threat activity seen on the top 50 web hosting services. That list featured several of the main players like Windows.net, Wordpress.com, Bluehost, Wix, Google’s Firebase and many others. Here’s the graph that shows web hosting platforms with security risks on subdomain:

Legitimate Services Used for Phishing Campaigns

Turning our attention to phishing, we’ve come across phishing campaigns where hackers leverage various Cloudflare services: Pages to deploy static webpages, and they take advantage of Workers to deploy serverless code to multiple potential locations around the globe. And bad actors also take advantage of the Cloudflare CDN to speed delivery of SaaS apps anywhere in the world.

We’ve observed significant levels of activity on the Windows.net domain where hackers leverage Azure Blob Storage to host and serve static web content, files and applications. Attackers take advantage of this by hosting phishing pages, malware, or tech support scams on subdomains like web.core.windows.net or azurewebsites.net. These subdomains make the malicious content appear more credible because they are associated with Microsoft’s trusted infrastructure.

And of course, hackers also rely on open-source services like IPFS. Its decentralized nature makes it harder to take down web pages, files or applications since they are spread across multiple servers. Hackers count on the fact that traditional web-hosting takedown methods (like contacting the hosting provider) don’t work effectively with IPFS, as the content is distributed across many nodes.

Attackers use rotating malicious URLs, hosted on platforms like AWS or Azure, to evade detection and blocking.

Hackers Thinking Like Digital Marketers

For phishing campaigns, attackers will sometimes put on their digital marketing hats. In this regard, they resort to tactics like SEO poisoning, where they’ll use popular or trending keywords in the content of their malicious websites to trick search engines into ranking them higher. These keywords are often related to current events, popular software or security concerns (e.g., "free antivirus," "Google Authenticator," etc.).

Speaking of thinking like digital marketers, hackers also use Google Ads to promote their wares to unsuspecting victims. We’ve observed scenarios where they impersonate items from Google's product line, such as Google Authenticator, or Google Maps for example. They’ll use Google’s Looker Studio to create fake home pages. On those fake pages, they’ll display images that resemble what you’d expect on the Google search page, to trick users into interacting with the fake page. They’ll use ads to lure users to these fake Google pages.

Malware Categories Trend Heading into 2025

We compared different malware categories detected via our real-time signatures over the last several months to get a sense for what malware categories will trend in 2025. In the graph below, the number of malicious websites more than quadrupled from less than 100,000 in Q1 2024 to nearly 500,000 instances at the end of Q3. We expect that trend to continue. Phishing and scams represented the second most by volume, growing from about 125,000 instances in Q1 to almost 400,000 by the end of Q3 2024. By comparison, we expect the compromised website category to continue to lag those leading malware categories.

Forcepoint DLP

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