Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d806cfc69b09b789…

MALICIOUS

RTF / .DOC

31.4 KB First seen: 2023-03-23
MD5: 23c2675b4931301f0e5894230f9252df SHA-1: 85c68b857bfae67a792093bac78e1c2069e1af8d SHA-256: d806cfc69b09b789a24288486f894e7d4e24e06d731f143f5033f67d0cb9cc9a
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, a known technique for exploiting vulnerabilities like CVE-2017-11882. The document also contains a lure instructing the user to 'Enable editing', which would activate the OLE object and likely trigger the exploit. No specific malware family is identifiable from the provided evidence.

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_off00005836.bin
be23e8012f9e36b5e9b52633aafdb7b39c48cc821f1a25e8689695c2e6c2431e
rtf-objdata-decoded RTF \objdata at offset 0x5836 1437 bytes