Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5d6ebddc0f862adf…

MALICIOUS

RTF / .DOC

4.1 KB
MD5: d5dd676762317bfaacccfeb8d82f8367 SHA-1: f6d80afeb028f04b542db9a3032be829e47fbd05 SHA-256: 5d6ebddc0f862adf831954ac82f4f36884261cdea3f172027cad50e704079748
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF document contains an embedded OLE object that leverages the Equation Editor vulnerability (CVE-2017-11882). The presence of ".objdata" and ".objupdate" sections, along with the specific Equation Editor ProgID, strongly indicates exploitation for client execution. This is a common technique for delivering malicious payloads via email attachments.

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_off000000ab.bin
fca82ee87551d357947953dc34970ca076fbfb1a689e29d1c8071c1891ff648c
rtf-objdata-decoded RTF \objdata at offset 0xAB 1830 bytes