Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 3a2d4def8df0e2a3…

MALICIOUS

RTF / .DOC

54.0 KB
MD5: 589f61bf68b88c20ed3097db98e2eb26 SHA-1: e54585484dac4b50f8f4e5c777158d3114f2cf81 SHA-256: 3a2d4def8df0e2a34ab0e2cc126c8e00857bd556356f2c6f4137fa19e3d33b2d
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 embedded OLE objects and specifically triggers the Equation Editor vulnerability CVE-2017-11882. This indicates the document is designed to exploit this known vulnerability, likely leading to arbitrary code execution upon opening. The presence of ".objdata" and ".objupdate" sections further confirms the malicious intent of activating embedded objects.

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_off00001d8f.bin
a0eef208b2a63f04cf5c74dd7da382f383cf0ff8c7b0ce9de8aebaf1dc75ba07
rtf-objdata-decoded RTF \objdata at offset 0x1D8F 1750 bytes