Malicious RTF — malware analysis report

Static analysis result for SHA-256 61f08d58dbabaf60…

MALICIOUS

RTF

51.8 KB First seen: 2023-09-08
MD5: 36a2ef1b4b46f1bded1bdc073ee3195a SHA-1: fe64a25f50edef0cbd0d96019a793468b82f21b4 SHA-256: 61f08d58dbabaf6063f3f3b44fdf26b4acf5a7d43e5e17e55bffbe7fa92801db
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File

The RTF file contains OLE object data and specifically targets the Equation Editor, indicating an attempt to exploit a known vulnerability. The presence of \objupdate and a lure to 'Enable editing' strongly suggests the document is designed to trigger an exploit upon opening, likely leading to further malicious execution. No scripts were extracted, and the document body content is generic financial text, not directly contributing to the exploit mechanism.

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_off00002c8f.bin
a8819e7c33bcfed70ead324ea3f64dabc4f4f9bf9161fbd589261e43301a88f3
rtf-objdata-decoded RTF \objdata at offset 0x2C8F 1741 bytes