Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 561d3479d4d5f1d1…

MALICIOUS

RTF / .DOC

24.8 KB First seen: 2022-11-14
MD5: 933953813a2efeea2151172036bb3a3f SHA-1: b292ac28f6842d7718fd013b17bfce1e580c8f80 SHA-256: 561d3479d4d5f1d1c8db891e0d55eb84b8d1a8c6c5a29caae9f80dcfed64fb2b
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.001 Spearphishing Attachment T1059.005 Visual Basic

The sample is an RTF document containing an embedded OLE object with a split Equation Editor ProgID, indicating a likely exploit attempt. The document body contains a lure instructing the user to 'Enable editing', a common tactic to bypass security measures and execute embedded malicious content. The presence of RTF_OBJDATA and RTF_OBJUPDATE heuristics further supports the exploitation of OLE object vulnerabilities.

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_off00004fde.bin
c757034d88b5e05585fa0a8971c5dffbd918f13a85dd840428e5e16c7011a313
rtf-objdata-decoded RTF \objdata at offset 0x4FDE 1383 bytes