Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2c2da23cd6a2d23d…

MALICIOUS

RTF / .DOC

42.1 KB First seen: 2023-02-13
MD5: 94cdeaf96c618dccfdf017804c79a526 SHA-1: 72dd89cfa70a2618415635263816acd07f5310cc SHA-256: 2c2da23cd6a2d23de30d17d4cb27fc74819cc54cd1d48f7bf3ce62b634afd4d3
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, triggered by \objupdate, which is a known exploit technique. The document also contains a lure instructing the user to 'Enable editing', indicating a social engineering attempt to bypass macro security. No scripts were extracted, and the document body content is unrelated to the exploit.

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_off000041ed.bin
645c4edf4211bb3eff9b4699aa4d454fefaf5e180dd31fc9923c2a19cbd99297
rtf-objdata-decoded RTF \objdata at offset 0x41ED 2191 bytes