Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 49fb6ddf765386b6…

MALICIOUS

RTF / .DOC

29.3 KB First seen: 2023-01-23
MD5: 282345d4e1bee33f4a659ca58934faf3 SHA-1: b8753f427fc310ec21ee3d74de90d7a2511198bd SHA-256: 49fb6ddf765386b676ba3b57486395947cb500c0d19bb23704c7d4beecc0a40e
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059.005 Visual Basic

The sample is an RTF document that exploits the Equation Editor vulnerability. The document body contains a lure, instructing the user to 'Enable editing' to view the content, which is a common technique for macro-based malware droppers. The presence of OLE object data and the specific RTF_EQUATION_EDITOR heuristic strongly suggest exploitation of a known vulnerability to execute arbitrary code.

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_off00004388.bin
4614362d90237c0ea15aa0c0485e7f069a9b48971a20dcb45f8a0cbffdceb25f
rtf-objdata-decoded RTF \objdata at offset 0x4388 1504 bytes