Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 146d6791ecd4d106…

MALICIOUS

RTF / .DOC

15.2 KB First seen: 2023-03-16
MD5: 793da24a8d4ec6573580c843f761796e SHA-1: cc2667dff50eb2c13cda77e569e3dd6582129372 SHA-256: 146d6791ecd4d1065f9f0f7a3c8a666644972f7fe37a34a50475fc36c5a8b535
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit the Equation Editor vulnerability. The document also contains a lure to enable editing, a common tactic for macro-based malware droppers. No scripts were extracted, and the document body content is benign financial advice, suggesting the exploit is the primary malicious component.

Heuristics 5

  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \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.
  • 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
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00002188.bin
db91f3745d4bea15d99a15869c2a8e9e0654473285eaa4b2b9370666d7feb373
rtf-objdata-decoded RTF \objdata at offset 0x2188 1527 bytes