WorkersDevBackdoor and MadMxShell converge in malvertising campaigns

Two malvertising campaigns target IT staff with two backdoors, MadMxShell and WorkersDevBackdoor, using shared infrastructure that links their delivery and C2 domains. The operation leverages Google ads, a Dropbox-hosted payload flow, and DNS-based C2, with evidence of infrastructure overlap and a single actor email tying multiple domains together. #MadMxShell #WorkersDevBackdoor #getstorege #goodgoog1e

Keypoints

  • Two malware payloads, MadMxShell and WorkersDevBackdoor, are distributed via malvertising campaigns aimed at IT staff.
  • MadMxShell uses DLL hijacking and DNS-based C2 (via OneDrive.exe), and is distributed through IP-scanner ads.
  • WorkersDevBackdoor is hosted on Dropbox with an NSIS installer that bundles an encrypted 7z payload, linked to ThunderShell/Parcel RAT in prior reporting.
  • Both campaigns share infrastructure and domain registrations (e.g., goodgoog1e), suggesting overlapping actors and delivery paths.
  • A PowerShell-based dropper (soft_detect.ps1) targets common IT tools to tailor installation and help evade sandbox detection.
  • The campaigns demonstrate infrastructure overlap across ASNs and domains, linking distribution and C2 components.

MITRE Techniques

  • [T1189] Drive-by Compromise – Malvertising campaigns deliver payloads via malicious ads. “Distributed via malicious ads for IP scanners”
  • [T1105] Ingress Tool Transfer – The distribution includes a one-liner that triggers an automatic download. “produces a one-liner that triggers an automatic download”
  • [T1574.001] DLL Search Order Hijacking – The MadMxShell payload is delivered via DLL hijacking. “Uses DLL hijacking”
  • [T1071.004] Application Layer Protocol: DNS – C2 communications use DNS with a domain pattern. “DNS for communication with its C2 server via OneDrive.exe”
  • [T1027] Obfuscated/Compressed Files and Information – Payload packaged in a password-protected 7z archive and delivered via NSIS. “encrypted 7z archive containing payload”
  • [T1497] Virtualization/Sandbox Evasion – PowerShell-based checks are used to avoid sandbox/VM detections. “PowerShell scripts… allow attackers to avoid unnecessary log alerts generated by malware running in sandboxes or virtual machines.”

Indicators of Compromise

  • [Domain] Malvertising-related domains – advanc3d-1p-scan[.]com, angryipscat[.]org, and other related domains
  • [Domain] C2/Infrastructure domains – litterbolo[.]com, getstorege[.]com, angryipo[.]org, and other related domains
  • [Hash] MadMxShell – 2481ac76f08d691166a425a01cdf1ec8ab5e2fbdf451c1bfc3edcba3e4c482e5 (ZIP), 93962847285d6f81273132e72d66b03a2e6e1a0ff46893e58ad3747762548922 (DLL), and 4 more hashes
  • [Hash] WorkersDevBackdoor – 55d1a76e4ed7d6ed0018c8129d631a637b591e18e52128dbe891a4382564793b, a8b0e013bd0d350035f12fd6703f7760a87cb218803e68c0eb482753961f2a41, 2264d2a23f365af0830b577360a724798a6132b1a2f4cd08a7ccfaa311ee920a
  • [URL] Dropbox URLs – dropbox[.]com/scl/fi/z6tdyz5n9hon8ae5nihzt/ipscan-3[.]9[.]1-setup[.]exe, dropbox[.]com/scl/fi/q1xoadn14acxg4wqf5k7s/ipscan-3[.]9[.]1-setup[.]exe, and 3 more URLs
  • [URL] Dropbox URLs – dropbox[.]com/scl/fi/eghhcp5hi7y22ok662mud/ipscan-3[.]9[.]1-setup[.]exe, dropbox[.]com/scl/fi/0om3wuhw9cqfip7gez6il/ipscan-3[.]9[.]1-setup[.]exe
  • [C2] Getstorege domain – getstorege[.]com (C2 domain registering activity linked to MadMxShell)

Read more: https://www.threatdown.com/blog/workersdevbackdoor-and-madmxshell-converge-in-malvertising-campaigns/