Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ea4ae17380630b5d…

MALICIOUS

RTF / .DOC

30.6 KB First seen: 2023-04-27
MD5: 6f1674e8c3136544e5a6195e407661b4 SHA-1: d0a00241ffc74e7317c14cdf8cec7a48e2b36623 SHA-256: ea4ae17380630b5d401502c36c18d9a5364b6e44b9286046a30df611d103ce6d
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit the Equation Editor vulnerability. The document also contains a lure instructing the user to 'Enable editing', which is designed to trigger the OLE object activation and subsequent exploit. This combination strongly suggests a malicious document designed for initial compromise.

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_off00004dc1.bin
fe422eff82243a73211c5824872a893607e703b0df5181f61efe4fd7a7bd0eb7
rtf-objdata-decoded RTF \objdata at offset 0x4DC1 1428 bytes