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.
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.
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.
CryptoBit: Another Ransomware Family Gets an Update
Palo Alto Unit 42 analyzes updated CryptoBit ransomware distributed via the Rig exploit kit, documenting IOCs, eight sample hashes, and disguise tactics from June 2016.
Unit 42 observed an updated CryptoBit ransomware variant (also tracked as CriptoBit or Mobef) delivered through the Rig exploit kit via the gate domain realstatistics.info between June 17-27, 2016. Infections targeted Windows hosts with out-of-date Flash plugins, and post-infection callbacks used fake user-agents and referrers to disguise traffic to laoismacau.com. At least eight samples were collected, and by June 27 the campaign had begun distributing other malware.
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.
Upatre Continued to Evolve with new Anti
Unit 42 analyzes an undocumented Upatre downloader variant with VM detection via process hashing, packed code, disabled Windows defenses and Namecoin .bit C2 domains.
Unit 42 analyzed an Upatre downloader variant compiled in December 2016 that went largely undetected by automated systems, featuring heavy code flow obscuration, on-demand decryption of network communications, and novel virtual machine detection. The sample enumerates running processes, computes CRC32 hashes XORed with a hard-coded key, and sleeps if analysis-related processes such as vmtoolsd.exe or python.exe are found. It masquerades with Google Chrome icons, disables Windows Defender, Firewall and other security services, injects code into msiexec.exe, and resolves .bit Namecoin domains like bookreader[.]bit via hardcoded OpenNIC DNS servers over TCP.
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.
Afraidgate: Major Exploit Kit Campaign Switches from CryptXXX Ransomware Back to Locky
The Afraidgate exploit kit campaign stopped distributing CryptXXX and now delivers the .zepto Locky variant exclusively through Neutrino EK since July 2016.
By mid-July 2016, the Afraidgate campaign switched from CryptXXX ransomware to consistently delivering the .zepto (Zepto) variant of Locky, using the Neutrino exploit kit after Angler EK disappeared in early June 2016. The campaign starts from compromised websites with injected scripts that redirect to Afraidgate domains and then Neutrino EK landing pages on .top domains. Zepto emerged after the Necurs botnet returned from a three-week outage, bringing new anti-sandboxing and evasion techniques.