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Decline in Rig Exploit Kit

Rig exploit kit activity dropped roughly 75% after the pseudo-Darkleech and EITest campaigns stopped using EKs, reflecting an overall decline in exploit kit activity.

Rig EK activity fell sharply in 2017: the pseudo-Darkleech campaign disappeared at the end of March, cutting Rig traffic about 50%, and the EITest campaign switched to tech support scams in late April, cutting another 50% in May. Broader causes include a shrinking browser target base, no major EK zero-day in over a year, and community takedowns of domain shadowing infrastructure. Criminals are shifting to malspam, social engineering schemes like fake HoeflerText notifications, and tech support scams.

Palo Alto Unit 42 · Aug 17, 2026Exploit / PoC in the wild1

Campaign Evolution: pseudo

Unit 42 traces the pseudo-Darkleech campaign's 2016 shift from Angler to Neutrino to Rig exploit kits and rotating ransomware payloads.

Unit 42 documents how the pseudo-Darkleech exploit kit campaign evolved through 2016, switching from Angler EK to Neutrino EK in June and to Rig EK in September after Neutrino ceased operations. Payloads rotated from TeslaCrypt to CryptXXX, CrypMIC, and finally Cerber ransomware by October 2016. Injected script on compromised websites changed from 12,000-18,000 character obfuscated blocks to short, unobfuscated hidden iframes starting July 1, 2016.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

Campaign Evolution: EITest from October through December 2016

Unit 42 details the EITest campaign's late-2016 changes: gates and obfuscation dropped, with Rig EK variants delivering ransomware and infostealers.

Unit 42 tracks the EITest campaign through late 2016, noting it abandoned the gate between compromised websites and exploit kit landing pages after its October 2016 report, and stopped obfuscating injected script URLs by October 15. The campaign primarily uses the Rig-E (Empire Pack) variant and sometimes Rig-V of Rig EK to deliver Cerber and CryptoMix ransomware plus infostealers such as Gootkit, the Chthonic banking Trojan, Ursnif variants, and Latentbot. Tracked since 2014 by Malwarebytes Labs and others, EITest targets unpatched Windows systems without specific victimology.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

Campaign Evolution: Darkleech to Pseudo

Unit 42 traces the pseudo-Darkleech campaign, which compromises websites to inject scripts redirecting visitors to exploit kits delivering ransomware.

Palo Alto Networks Unit 42 analyzed the evolution of the pseudo-Darkleech campaign, which injects malicious script into compromised Apache, IIS and WordPress sites to redirect visitors to exploit kits such as Angler and Neutrino. The original Darkleech Apache module infected thousands of servers starting in 2012 and delivered Blackhole EK until that kit disappeared after Paunch's 2013 arrest. From 2015 onward, pseudo-Darkleech delivered ransomware families like CryptoWall and TeslaCrypt, and by early 2016 its injected scripts added obfuscated numeric blocks with frequently changing separator characters. Unit 42 tracks these patterns to help defenders identify compromised websites.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

EITest Campaign Evolution: From Angler EK to Neutrino and Rig

Unit 42 details the EITest campaign's shift from Angler to Neutrino and Rig exploit kits while distributing ransomware, downloaders, and banking trojans.

Unit 42 updated its tracking of the EITest campaign, first identified in October 2014, which compromises websites with injected scripts that redirect victims through a gate to exploit kits. After Angler EK disappeared in June 2016, EITest switched to Neutrino and then primarily used Rig EK by August 2016. In September 2016 the campaign began using hex-obfuscated JavaScript and simplified gate URLs, while continuing to distribute payloads including Gootkit, Cerber, Bart, CryptFile2, Vawtrak, Ursnif, and Tinba. Gate infrastructure consistently reused IP blocks such as 85.93.0.0/24 even as domain names changed.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

Understanding Angler Exploit Kit

Unit 42 examines Angler EK operations, including rapid zero-day adoption, fileless Bedep infections, and ransomware payloads like TeslaCrypt and CryptXXX.

Unit 42 published the second part of its Angler EK analysis, covering the kit's history since 2013, its SaaS rental model, and its focus on Flash, Internet Explorer, and Silverlight exploits. Angler integrated the CVE-2015-5119 Flash zero-day from the Hacking Team leak within hours and later added exploits for CVE-2015-2419 and CVE-2016-0034 roughly a month after Microsoft patched them. Campaigns use Angler to deliver ransomware such as CryptoWall, TeslaCrypt, and CryptXXX, plus banking trojans and stealers via EITest. Since August 2014, Angler has used fileless, in-memory execution, most often for Bedep, which later downloads CryptXXX and click-fraud malware.

Palo Alto Unit 42 · Aug 17, 2026Research in the wildCVE-2015-5119CVE-2015-2419CVE-2016-0034

Malspam Targeting Brazil Continues to Evolve

Brazilian malspam campaigns continue evolving, abusing Google URL shortener and Dropbox and using Squiblydoo plus DLL side-loading to deploy likely infostealing botnet malware.

A June 2017 Brazilian malspam campaign spoofed IPTU tax notification emails, using the recipient's address as the sender, and abused Google's URL shortener and Dropbox to deliver a zip containing a malicious Windows shortcut (.lnk) file. The LNK used the Squiblydoo technique (regsvr32.exe) to download and execute a scriptlet with elevated privileges, retrieving a signed G-Buster Browser Defense executable alongside a malicious fltLib.dll loaded via side-loading, likely an information-stealing botnet. Post-infection HTTP traffic exposed over 400 infected Windows hosts, mostly in Brazil, with 2,132 Banload-tagged samples observed in the first half of 2017.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild