Malicious RTF — malware analysis report

Static analysis result for SHA-256 ba534f6c76b1819d…

MALICIOUS

RTF

1.7 KB Authoring application: Riched20 6.3.9600 First seen: 2020-12-28
MD5: 399c7aac3c38003b0ff38eba153e4e17 SHA-1: 375d35bba263b4574fe42797801b5ccbbcbb0fd7 SHA-256: ba534f6c76b1819d4246abb8f0a5947dfa25187e8e33cfe7aa0adf390fe2d306
280 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains embedded OLE object data and specifically targets the Equation Editor, indicating an exploit for CVE-2018-0802. This vulnerability allows for the execution of arbitrary code when the embedded object is activated, likely delivered via spearphishing.

Heuristics 7

  • Equation Editor ProgID + OLE object high CVE related RTF_EQUATION_EDITOR
    RTF references Equation.3 ProgID alongside \objdata — likely Equation Editor (CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798) but without the binary CLSID payload, so flagged at HIGH instead of CRITICAL.
  • ClamAV: Rtf.Exploit.CVE_2018_0802-6624871-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2018_0802-6624871-1
  • Equation Editor object class critical RTF_OBJCLASS_EQUATION
    Object class 'equation.3' references Equation Editor
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • OLE object data medium RTF_OBJDATA
    RTF contains 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000fe.bin rtf-objdata-decoded RTF \objdata at offset 0xFE 693 bytes
SHA-256: 009cbf77c28f52f82500eeaa3c7e569278d9b85682be0c566782f8cb5de2c239
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): powershell.exe -noexit -windowstyle maximized