Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6ee894977bb2a47f…

MALICIOUS

RTF / .DOC

17.9 KB
MD5: 9f262c6d365ac4bc1b8785009bbe1368 SHA-1: 81a240b1cc12340d0d003af33bf6e4a1c93154fe SHA-256: 6ee894977bb2a47f9fff347a6e29942065c1058a3a0dfd924884af1c3320d569
180 Risk Score

Malware Insights

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

The sample is an RTF document that contains embedded OLE object data, specifically triggering critical heuristics for CVE-2017-11882 via an Equation Editor vulnerability. This exploit is known to allow for arbitrary code execution, which is likely used here to download and execute a secondary payload. The presence of the ".objupdate" directive further suggests an attempt to force OLE object activation.

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.
  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001dcc.bin
d920eab6f0fadfdb952841fb0fbf30876f0beb7c79a405570e1a802db752307e
rtf-objdata-decoded RTF \objdata at offset 0x1DCC 4166 bytes