Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 113c028ff85ee687…

MALICIOUS

RTF / .DOC

39.1 KB First seen: 2023-04-14
MD5: abf058dadfc0026bcadf1df05366950c SHA-1: 88830ceb65b7cc2852ce7617f8bbd1e1431ba810 SHA-256: 113c028ff85ee687dfc0c652166d470c8f6d00939bae012e20ebb0baecded63d
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566.001 Phishing: Spearphishing Attachment

The file is an RTF document containing an embedded OLE object that exploits a known vulnerability in the Microsoft Equation Editor. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics indicates an attempt to trigger code execution via the embedded object. The `SE_ENABLE_LURE` heuristic suggests the document likely contains a prompt to enable editing or macros, a common social engineering tactic to bypass security measures and facilitate 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_off00005881.bin
b8e01191e434a62b9285b2d429ffd41784bb5d5fd6dbdd4d47c952561b49b3b2
rtf-objdata-decoded RTF \objdata at offset 0x5881 1925 bytes