Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 72741fbda226683f…

MALICIOUS

RTF / .DOC

28.0 KB First seen: 2022-11-28
MD5: 532676a539f1be2b2b5132724a593f3d SHA-1: 3b5c05bcd36be469400aaf08e84cf959b02c10bf SHA-256: 72741fbda226683f04a4966fe43d16d963aa22991521c27212db349b8cef3362
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, and an \objupdate directive that forces OLE activation. This strongly suggests an attempt to exploit a vulnerability, likely CVE-2017-11882, through a social engineering lure to enable editing. No scripts were extracted, and the document body content appears to be unrelated academic text, serving as a distraction.

Heuristics 4

  • 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
  • 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_off0000546b.bin
d818fd3181ba401e87d34d056f1b7ea510ee3b8716e05e388015d1db09d83a83
rtf-objdata-decoded RTF \objdata at offset 0x546B 1999 bytes