General

  • Target

    Chernobyl.exe

  • Size

    423KB

  • Sample

    240303-ybb29sff26

  • MD5

    493a80432585b0ed66493d19bfd760fe

  • SHA1

    55dc4b662bc0cbbb46bef2e2c0b42f29e708d861

  • SHA256

    3df8578b571811a77eefdf07069bd4d1ba16af70dba81bcf91d8182171728f74

  • SHA512

    c699d41189692149d8e15f18494b78db2caf890502906bc5576a9db9ab102970b89010f8cf85cef9e7ee1e5c6b60f88a3179d26d04cdfa88d26d598deb0636f9

  • SSDEEP

    6144:O1b/8Io02222222222222222222222222222222222222222222222222222222y:OqtH0tOZzv4TatsNqaJR

Malware Config

Targets

    • Target

      Chernobyl.exe

    • Size

      423KB

    • MD5

      493a80432585b0ed66493d19bfd760fe

    • SHA1

      55dc4b662bc0cbbb46bef2e2c0b42f29e708d861

    • SHA256

      3df8578b571811a77eefdf07069bd4d1ba16af70dba81bcf91d8182171728f74

    • SHA512

      c699d41189692149d8e15f18494b78db2caf890502906bc5576a9db9ab102970b89010f8cf85cef9e7ee1e5c6b60f88a3179d26d04cdfa88d26d598deb0636f9

    • SSDEEP

      6144:O1b/8Io02222222222222222222222222222222222222222222222222222222y:OqtH0tOZzv4TatsNqaJR

    • Contains code to disable Windows Defender

      A .NET executable tasked with disabling Windows Defender capabilities such as realtime monitoring, blocking at first seen, etc.

    • Modifies WinLogon for persistence

    • UAC bypass

    • Disables RegEdit via registry modification

    • Disables Task Manager via registry modification

    • Possible privilege escalation attempt

    • Modifies file permissions

    • Modifies system executable filetype association

    • Checks whether UAC is enabled

    • Modifies WinLogon

    • Writes to the Master Boot Record (MBR)

      Bootkits write to the MBR to gain persistence at a level below the operating system.

    • Drops file in System32 directory

    • Sets desktop wallpaper using registry

MITRE ATT&CK Enterprise v15

Tasks