Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0bbd18d6b2489f5b…

MALICIOUS

RTF / .DOC

14.8 KB First seen: 2022-10-06
MD5: fce9707f8a2cac99cb3213dd7c20c5e0 SHA-1: 7102a4c6b8e5a88bb7a1f4618fe137ecdb7cdae7 SHA-256: 0bbd18d6b2489f5b80dc6efe820d0fc6065e9242bf95f75667897bc6da750954
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability. The presence of \objupdate indicates an attempt to force activation of this embedded object. The document body contains a lure instructing the user to 'Enable editing', a common tactic to bypass macro security settings and facilitate exploitation.

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_off00000661.bin
7decd94d3d443c5dd4730bba672cc8435e6b87b57291a7815b5ba775298a3f67
rtf-objdata-decoded RTF \objdata at offset 0x661 2033 bytes