Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5b2e65ed209acd3e…

MALICIOUS

RTF / .DOC

26.9 KB First seen: 2023-03-21
MD5: 4ff264c2efd8c0bba69030aa6a5fe31e SHA-1: 67d1da5490277818ee07faaa22c6e0314a80c2ef SHA-256: 5b2e65ed209acd3ee8ccb08afa456e4672aae7e3b61760cdf9540cf38ec13994
140 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 CVE-2017-11882. The `SE_ENABLE_LURE` heuristic confirms the document instructs the user to enable editing, which would activate the OLE object and trigger the exploit. The `RTF_OBJUPDATE` heuristic further suggests that the object is configured to automatically update, facilitating the exploit execution.

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_off0000491b.bin
ac900608a3f4fb542980500725a33098c3fbf2347772b6046d3abaa894db689c
rtf-objdata-decoded RTF \objdata at offset 0x491B 1606 bytes