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Crooks Are Buying Your Expired Domains and Using Them to Deliver Malware


Crooks Are Buying Your Expired Domains and Using Them to Deliver Malware

Pierluigi Paganini
August 15, 2026

Attackers are buying expired domains to exploit their reputation, traffic and DNS history, using them for malware delivery, scams and C2 infrastructure.

Every day, roughly 65,000 domain names that once belonged to someone else get re-registered by a new owner. Infoblox Threat Intel calls these dropcatch domains, and in the first half of 2026 they accounted for nearly 20% of all new domain registrations, meaning one in five “new” domains has a prior life. Some end up with legitimate investors or researchers. Others end up with attackers who have figured out that a domain with history is worth more than a blank slate.

“These domains can be particularly interesting, even dangerous, because they inherit reputation and sometimes connections from their previous life. For example, a domain that was originally registered 10 years ago, later dropped, and then acquired by someone else may still carry signals associated with its long history.” reads the report published by Infoblox. “Researchers, security products, and reputation-based algorithms may view it more favorably than a genuinely brand-new registration. Threat actors know this and take advantage of it.”

Among gTLDs, the average is 50,400 per day, with 15 TLDs accounting for about 92% of all dropcatch activity. .net and .xyz have the highest rates, with nearly 30% of new registrations previously registered, while .com reaches 24.5%. Determining who buys these domains and how they are used remains difficult due to WHOIS privacy, transfers, parking, and auctions.

The inherited value isn’t just a better reputation score. Expired domains also come with residual web traffic from old backlinks, email still arriving for the previous owner, cached search results, and in some cases lingering DNS records that point to infrastructure no longer under the original owner’s control. One in every five new domains has all of that already baked in before the new registrant does anything.

Infoblox tracked one threat actor it calls Sable Squirrel, which has spent nearly $7 million acquiring expired domains to build a criminal operation spanning illegal sports streaming, gambling promotion, and malware infrastructure. The actor controls more than 10,000 domains and runs streaming platforms under brands like Xoilac, Cakhia, and 90phut that direct Vietnamese, Korean, Japanese, and Australian users toward betting sites, while a subset of those same streaming domains double as command-and-control servers for malware including Quasar RAT, AsyncRAT, DCRat, and Remcos RAT. Among the expired domains Sable Squirrel has acquired are healthymagination.com, originally a General Electric health initiative, and rezilion.com, a cybersecurity company whose assets were sold to GitLab in 2024. The actor bought the reputation of a defunct infosec firm and pointed it at malware infrastructure — which is either darkly ironic or exactly what you’d do if you understood how security tools evaluate domain age.

“For threat actors specifically, the inherited reputation isn’t the only thing valuable about acquiring a dropped domain. They also come with a variety of lingering connections: email intended for the original domain holder (see watchTowr Labs’ The Perils of Expired Domains: We’re Reading Your Email), cached search results, inherited web traffic, and in some cases, a ready-made platform for code injection on already compromised sites.” continues the report. “Lingering DNS records can also create opportunities for threat actors. We previously discussed dangling CNAME attacks in our blog post, Who Knew Domain Hijacking Is So Easy?.”

Once Sable Squirrel re-registers a domain, it moves fast: 24% go live the same day, 76% within seven days, 94% within two weeks. The whole point is to start capturing traffic before security systems have updated their assessments.

Infoblox is also tracking three scavenger actors, Stuffy Squirrel, Shady Squirrel, and Swiping Squirrel, that operate differently: rather than buying domains wholesale for a planned operation, they acquire expired domains that were previously compromised by other attackers and simply inherit the existing infection traffic. Shady Squirrel, assessed to be Russian-speaking and active since at least July 2023, feeds that traffic to SocGholish and tech support scam networks. SocGholish reportedly regained access to thousands of compromised sites by teaming up with Shady Squirrel days after its own infrastructure was disrupted by law enforcement. The practical lesson for defenders is uncomfortable: domain age and reputation are inputs worth questioning, not trusting, because an old domain in new hands is only as trustworthy as whoever currently holds it.

“This is just one story of how threat actors use dropcatch domains to further their schemes. We’ll cover many more in the next two parts of this research: Part 2, $7 Million in Expired Domains Fuel a Streaming Empire with a Malware Secret, where we examine Sable Squirrel, a threat actor that has spent millions of dollars acquiring dropped domains, and Part 3, Dropcatch Scavengers: Expired Malicious Domains Become Cash Cows, where we explore actors that scavenge expired malicious domains and inherit traffic from previously compromised websites.” concludes the report.

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Pierluigi Paganini

(SecurityAffairs – hacking, Expired domains)







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