Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a9c079c283fc38c4…

MALICIOUS

RTF / .DOC

54.2 KB First seen: 2023-06-14
MD5: dc82b4273b5dea74f79af07769ada3cd SHA-1: 4f5ecbd57dcc6ae159b86d4a08f86b0bccd6d4e7 SHA-256: a9c079c283fc38c4a400ed02cd39e4095beb83e8ba30f89d0d5649435d7cec3e
180 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, a known exploit technique. The 'SE_ENABLE_LURE' heuristic indicates the document instructs the user to enable editing, which would trigger the OLE object's activation and likely exploit the Equation Editor vulnerability. This suggests a delivery mechanism for a malicious payload.

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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off00007d80.bin
e67ef005e15ad574bdd15df9be2c570ccdf02641ad4196223847266ddf00f20d
rtf-objdata-decoded RTF \objdata at offset 0x7D80 1719 bytes