"Blank Slate" Campaign Takes Advantage of Hosting Providers to Spread Ransomware
Unit 42 profiles the Blank Slate malspam campaign: blank emails with double-zipped attachments delivering Cerber ransomware while cycling abused hosting provider domains.
The Blank Slate campaign sends empty emails containing double-zipped archives with macro-enabled Word documents or JavaScript files that launch PowerShell to download ransomware, primarily Cerber, and occasionally Sage 2.0 or Locky. Unit 42 observed 555 campaign domains over seven months, with actors repeatedly registering new domains and cycling abuse of legitimate hosting providers after takedowns. In a five-day January-February 2017 window, at least eight domains across seven IP addresses were observed hosting Cerber payloads.
Threat Brief: Atlassian Confluence Remote Code Execution Vulnerability (CVE-2022
Unauthenticated Confluence RCE CVE-2022-26134 was exploited in the wild; Volexity observed intrusions and Cerber ransomware on unpatched servers.
Volexity identified exploitation of CVE-2022-26134, an unauthenticated remote code execution vulnerability in Atlassian Confluence Server and Data Center, during Memorial Day weekend 2022, with Atlassian issuing a patch. Cortex Xpanse found 19,707 potentially affected Confluence instances, concentrated in the US, Germany, China, and Russia, plus 1,251 end-of-life versions exposed. Unit 42 and Cortex Managed Threat Hunting observed successful exploitation leading to reconnaissance commands and a Cerber ransomware deployment that was blocked by Cortex XDR. A public PoC has increased exploitation risk.
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.
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.