Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0fb5b4aa13694548…

MALICIOUS

RTF / .DOC

26.8 KB First seen: 2022-11-14
MD5: 54f85b41a771870405946c88e5527534 SHA-1: 689dfaaad101f47d846655b0627e0487b4796051 SHA-256: 0fb5b4aa136945485a0c75c3269e53778f5a698beba5bc5f46a708e5a269a28d
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, which is a known exploit vector. The document also contains a lure instructing the user to 'Enable editing' to view its content, indicating an attempt to bypass security measures and trigger the exploit. No specific malware family could be identified.

Heuristics 4

  • 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
  • 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_off00005032.bin
409060095c1f53933302ec77ba6b667197735ad4a86bc6d9e3b0d3c107debc9d
rtf-objdata-decoded RTF \objdata at offset 0x5032 1942 bytes