Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 db8f4bfce01b625b…

MALICIOUS

RTF / .DOC

16.2 KB First seen: 2022-08-29
MD5: 0e7780c9df4f47a6d8fd59546d357db8 SHA-1: 4f3635ae7ccab0ef467c8339b68d608cadc43ea6 SHA-256: db8f4bfce01b625bb4431d0f951588304f0069676e1651948dd25c5f4b49aa37
160 Risk Score

Malware Insights

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

The file is an RTF document containing OLE object data, specifically triggering the Equation Editor heuristic. The presence of \objupdate indicates an attempt to force OLE activation, and the SE_ENABLE_LURE heuristic suggests the document prompts the user to enable editing or macros. This combination strongly suggests an exploit targeting the Equation Editor vulnerability to deliver a malicious payload.

Heuristics 5

  • Equation Editor CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • \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 2 \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_off000012ce.bin
a2dc200ba6cdf19413ceb7b8fa3f24086c324a378c94f1996331ddc717af2f8a
rtf-objdata-decoded RTF \objdata at offset 0x12CE 3729 bytes