Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 caaac2649b57e658…

MALICIOUS

RTF / .DOC

27.4 KB First seen: 2022-11-25
MD5: 8a87321a096ef3926c626e44fc58fb4c SHA-1: 9bec3b1a0fcb3369d9635351455afc944a5d0530 SHA-256: caaac2649b57e658e83daff19e510575c9a53b8fc91dd55aefd278191d00f2dc
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 a ProgID indicative of the Equation Editor vulnerability. The \objupdate directive suggests that the object will be activated upon opening, likely triggering an exploit. The document body contains a lure instructing the user to 'Enable editing', which is a common tactic for macro-based or exploit-laden documents.

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_off00005587.bin
127a86873c72c7f6ead6663cb0e952fbde824da18ca68b92e6bf971c2cb731d1
rtf-objdata-decoded RTF \objdata at offset 0x5587 1771 bytes