The menace actors behind the VexTrio Viper Site visitors Distribution Service (TDS) have been linked to different TDS providers like Assist TDS and Disposable TDS, indicating that the subtle cybercriminal operation is a sprawling enterprise of its personal that is designed to distribute malicious content material.
“VexTrio is a bunch of malicious adtech corporations that distribute scams and dangerous software program by way of completely different promoting codecs, together with smartlinks and push notifications,” Infoblox stated in a deep-dive report shared with The Hacker Information.
Among the malicious adtech corporations below VexTrio Viper embody Los Pollos, Taco Loco, and Adtrafico. These corporations function what’s known as a industrial affiliate community that connects malware actors whose web sites unsuspecting customers land on and so-called “promoting associates” who provide varied types of illicit schemes like reward card fraud, malicious apps, phishing websites, and scams.
Put otherwise, these malicious site visitors distribution techniques are designed to redirect victims to their locations by means of a SmartLink or direct provide. Los Pollos, per the DNS menace intelligence agency, enlists malware distributors (aka publishing associates) with guarantees of high-paying presents, whereas Taco Loco focuses on push monetization and recruits promoting associates.
One other notable element of those assaults is the compromise of WordPress web sites to inject malicious code that is chargeable for initiating the redirection chain, finally main guests to VexTrio rip-off infrastructure. Examples of such injections embody Balada, DollyWay, Sign1, and DNS TXT report campaigns.
“These scripts redirect web site guests to varied rip-off pages by means of site visitors dealer networks related to VexTrio, one of many largest identified cybercriminal affiliate networks that leverages subtle DNS methods, site visitors distribution techniques, and area era algorithms to ship malware and scams throughout international networks,” GoDaddy famous in a report revealed in March 2025.
VexTrio’s operations suffered a blow round mid-November 2024 after Qurium revealed that the Swiss-Czech adtech firm Los Pollos was a part of VexTrio, inflicting Los Pollos to stop their push hyperlink monetization. This, in flip, triggered an exodus, inflicting menace actors that relied closely on the Los Pollos community to maneuver to alternate redirect locations akin to Assist TDS and Disposable TDS.
 |
| Modifications in habits over time from the 2 unbiased C2 units |
Infoblox’s evaluation of 4.5 million DNS TXT report responses from compromised web sites over a six-month interval has revealed that the domains that have been a part of the DNS TXT report campaigns may very well be labeled into two units, every with its personal distinct command-and-control (C2) server.
“Each servers have been hosted in Russian-connected infrastructure, however neither their internet hosting nor their TXT responses overlapped,” the corporate stated. “Every set maintained completely different redirect URL constructions, though they each initially led to VexTrio and subsequently to the Assist TDS.”
Additional proof has uncovered that each Assist TDS and Disposable TDS are one and the identical, and that the providers loved an “unique relationship” with VexTrio till November 2024. Assist TDS, which traditionally redirected site visitors to VexTrio domains, has since shifted to Monetizer, a monetization platform that makes use of TDS know-how to attach net site visitors from writer associates to advertisers.
“The Assist TDS has a robust Russian nexus, with internet hosting and area registration often executed by way of Russian entities,” Infoblox stated, describing the operators as probably unbiased. “It doesn’t have the full-blown performance of the VexTrio TDSs and has no apparent industrial ties past its eerie connections with VexTrio.”
VexTrio is one among the many many TDSs which were outed as industrial adtech corporations, the others being Companions Home, BroPush, RichAds, Admeking, and RexPush. Many of those are geared in the direction of push notification providers by making use of Google Firebase Cloud Messaging (FCM) or Push API-based custom-developed scripts to distribute hyperlinks to malicious content material by way of push notifications.
“A whole bunch of hundreds of compromised web sites around the globe yearly redirect victims to the tangled net of VexTrio and VexTrio-affiliate TDSs,” the corporate stated.
“VexTrio and the opposite affiliate promoting corporations know who the malware actors are, or they at the very least have sufficient data to trace them down. Most of the corporations are registered in international locations that require a point of ‘know your buyer’ (KYC), however even with out these necessities, publishing associates are vetted by their buyer managers.”
