Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 3b660658eded7739…

MALICIOUS

RTF / .DOC

282.4 KB First seen: 2022-02-24
MD5: 5163f992525315cd44c1e23897bbb812 SHA-1: 78d3e137dd32eed1cbdde9be9cc0932acf6b4f81 SHA-256: 3b660658eded77390c2a90e1b5414c02872a23c8ba55add3c27c1bfee42492cf
123 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.001 PowerShell

The RTF document contains multiple OLE objects, with specific heuristics indicating the use of \objdata and \objupdate, suggesting an attempt to exploit OLE object activation. The presence of Composite Monikers further supports this, pointing towards a likely attack pattern involving the execution of embedded malicious code. No scripts were extracted, and the document body contained only formatting information, limiting further analysis of the specific payload.

Heuristics 4

  • Composite Moniker in RTF OLE object high CVE related RTF_COMPOSITE_MONIKER_RELATED
    RTF contains Composite Moniker CLSID in OLE object context, but no nearby scriptlet/SCT payload was confirmed. Treat as related moniker attack-surface evidence rather than proof of CVE-2017-8570 exploitation.
  • \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 3 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000007d0.bin
9fb9686dc078699084c9a015153c9fac33aa53dc05692ad1f158c089ce9dfaec
rtf-objdata-decoded RTF \objdata at offset 0x7D0 47644 bytes
objdata_01_off00018b8a.bin
893d8db8585190a273d0c7c3dcff2eb58184b866a3687a9319ca72a8284876cb
rtf-objdata-decoded RTF \objdata at offset 0x18B8A 2632 bytes
objdata_02_off0001a12d.bin
44deae4627fee3c44f54d5bd10477ec2e17f4c08135f08e2417832e36d10d037
rtf-objdata-decoded RTF \objdata at offset 0x1A12D 12297 bytes