Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 63a8fc1247dd5615…

MALICIOUS

RTF / .DOC

651.2 KB
MD5: 2c9c398b48a5dd09677fcc4e1fd801e1 SHA-1: 99a62ef8e1088516c1b9dc497d3f92a2eb455e85 SHA-256: 63a8fc1247dd5615235428bfe7eeed1abea8a1199071649cf575f43012dfcfdd
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is an RTF document that exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. The document body contains text that attempts to trick the user into enabling editing, which is a common lure for macro-based malware. The exploitation of the Equation Editor allows for arbitrary code execution, likely to download and run a secondary payload.

Heuristics 4

  • 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 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_off0000c05a.bin
0854f4cbca7afc852b8e16930401a68138b0c18c17d6a2de383ba58967b54eb3
rtf-objdata-decoded RTF \objdata at offset 0xC05A 4250 bytes