Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 03db28784d9f4e09…

MALICIOUS

RTF / .DOC

39.7 KB First seen: 2023-07-20
MD5: 35de3e6248be9a9f2c2094d07e44b585 SHA-1: 2b8268ab7035348e49b1c59e96c7d9d8ac79d9bb SHA-256: 03db28784d9f4e0920871f59991dda53f3179994ce1a0d18e72f5497728aa16f
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object, specifically targeting the Equation Editor, and includes a lure to enable editing. This strongly suggests an attempt to exploit a known vulnerability, such as CVE-2017-11882, to execute a malicious payload. The document body itself is a generic academic assignment, indicating it's likely a lure to disguise the malicious embedded content.

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_off0000441e.bin
86d076488f6074daf37baef4a22b305a6fbb085e0d2357b3e1b6f33fab731ba8
rtf-objdata-decoded RTF \objdata at offset 0x441E 1738 bytes