Malicious RTF — malware analysis report

Static analysis result for SHA-256 7d375ae3a5c0dddf…

MALICIOUS

RTF

37.7 KB First seen: 2023-07-11
MD5: f7c101969fb10e121abf500446015d73 SHA-1: 46f3f6d8e63be90e308c769aa464e58791d7aa03 SHA-256: 7d375ae3a5c0dddf7f868e78e39ca600b209b51c1852633fa7ce676f048d02ab
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object, specifically identified as an Equation Editor exploit. The presence of \objupdate and SE_ENABLE_LURE heuristics indicates the document is designed to trick the user into enabling content, which would then trigger the embedded object. This is a common delivery mechanism for exploiting vulnerabilities like CVE-2017-11882.

Heuristics 5

  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off00004835.bin
6740834d727bae53928f90c6d38f4c08ea5296c63c191f2767921df5bc826e1c
rtf-objdata-decoded RTF \objdata at offset 0x4835 1596 bytes