Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 4369a2729f0a7489…

MALICIOUS

RTF / .DOC

41.5 KB
MD5: 9b56693e37a46a7083049d26043c1e49 SHA-1: ebbdaf2a87d12a423e9e89ca66f6381d6e13393e SHA-256: 4369a2729f0a74892b91cc750e3e9faab1e392aa09e60525cc45f5259c74343b
120 Risk Score

Malware Insights

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

The sample is an RTF document that exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This is indicated by the critical heuristic firing for CVE_2017_11882 and the presence of OLE object data. The exploit likely allows for the execution of arbitrary code, enabling the delivery of a secondary malicious payload. The document body is heavily obfuscated and does not provide clear textual lures.

Heuristics 3

  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
  • \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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001734.bin
ec5f0614c11bc79e3c37bed9c043ee2e175b6be4fc635bcc69edb33e9282bfa0
rtf-objdata-decoded RTF \objdata at offset 0x1734 3643 bytes