Analysis of a Multi-stage Squiblydoo variant
The first foothold of the Malware was delivered via IP Address (IOC) 209.141.61.11. When the user navigates to that server, depending on the User-Agent string of the request, you’ll either get a signed, legitimate, non-malicious PDF document (Artifact #1 ZIP, 1d2d5b2befe5fcfea8e9303d87b92adaaf9f161a82e0e1341008518d1585e81a, VT 0/60) or a page with a simple CAPTCHA (Artifact #2 PCAP, dfed73960bd9aa030cc5d84df18eaf2d295dfa7f990614c53673e74b84034ef5, VT N/A) that ultimately leads to a ZIP file (Artifact #3 PCAP, 38dcef9b23f21a98fe9dde3f5b5eb643292bf41556b7e4d5da30484848c4cf3d, VT N/A and Artifact #4 ZIP, db647308649e2d3815f7d53d024ac50e8dead8a3caf33bc203dac90b5dbb1596, VT 15/61).
