General

  • Target

    Yashma ransomware builder v1.2.exe

  • Size

    826KB

  • Sample

    241219-vzz78awpgy

  • MD5

    20a7eea3f65edd41df1e3bbce7d2b674

  • SHA1

    44a9d957a24ab0e9f2066e9dfc4da8f9d46f0025

  • SHA256

    e505fe2a77857ac94c657999533631289dc76a1c62c73169232dfcd7a25990a9

  • SHA512

    bf3189616f1ed3ca3059fdbb9ea72c38a2e32804b0c5919f058d0798b928c4fd1ce3d015a4366c3f689bcfaa10d2f1fcd3a169c9e3ec6a68f4abdc47ef386fb0

  • SSDEEP

    6144:pMPUfXnG2omFLhFLuFL6FL6aGMVFLQYFWD/:pL3GcQZ

Malware Config

Targets

    • Target

      Yashma ransomware builder v1.2.exe

    • Size

      826KB

    • MD5

      20a7eea3f65edd41df1e3bbce7d2b674

    • SHA1

      44a9d957a24ab0e9f2066e9dfc4da8f9d46f0025

    • SHA256

      e505fe2a77857ac94c657999533631289dc76a1c62c73169232dfcd7a25990a9

    • SHA512

      bf3189616f1ed3ca3059fdbb9ea72c38a2e32804b0c5919f058d0798b928c4fd1ce3d015a4366c3f689bcfaa10d2f1fcd3a169c9e3ec6a68f4abdc47ef386fb0

    • SSDEEP

      6144:pMPUfXnG2omFLhFLuFL6FL6aGMVFLQYFWD/:pL3GcQZ

    • Chaos

      Ransomware family first seen in June 2021.

    • Chaos Ransomware

    • Chaos family

    • Deletes shadow copies

      Ransomware often targets backup files to inhibit system recovery.

    • Modifies boot configuration data using bcdedit

    • Deletes backup catalog

      Uses wbadmin.exe to inhibit system recovery.

    • Disables Task Manager via registry modification

    • Checks computer location settings

      Looks up country code configured in the registry, likely geofence.

    • Drops startup file

    • Executes dropped EXE

    • Reads user/profile data of web browsers

      Infostealers often target stored browser data, which can include saved credentials etc.

    • Adds Run key to start application

    • Drops desktop.ini file(s)

MITRE ATT&CK Enterprise v15

Tasks