Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 aeae4939ea6ffe1d…

MALICIOUS

RTF / .DOC

4.4 KB
MD5: 5415faf160b802e1e1b7e35dfc08ddfe SHA-1: 2ff126355be9521684d665eb643fc8854f08f539 SHA-256: aeae4939ea6ffe1d8ffbb4ab959d98753610b937a1894e6640ab6719a9325328
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF document contains an embedded OLE object specifically related to Equation Editor, triggering heuristics for CVE-2017-11882. The presence of \objupdate indicates that the OLE object is forced to activate upon opening the document. This exploit is known to download and execute arbitrary code, likely leading to further stages of infection.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000070.bin
f1a3455893ec139b1bdb1f2efe22f4f8b70e15489fdb637ac67251c94a5f04fe
rtf-objdata-decoded RTF \objdata at offset 0x70 1998 bytes