Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 1ec4a0b39d5167b6…

MALICIOUS

RTF / .DOC

4.9 KB
MD5: 293f9b74ffbf7eb1f756466a809b9bc9 SHA-1: 8f529fb120bf82ed9e4f426f4393be76a3fb0be2 SHA-256: 1ec4a0b39d5167b69c25e33c938bb345d76933cbad1af138dbfab82e50f30148
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an RTF document containing an embedded OLE object that leverages the Equation Editor. Heuristics indicate a high likelihood of exploitation for CVE-2017-11882, a known vulnerability that allows for arbitrary code execution. No specific family could be identified, and no external IOCs were extracted.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000b0.bin
bb703dd29707ff0296e63352a8de47926648262fb24dafa8c3b1af584d13d88d
rtf-objdata-decoded RTF \objdata at offset 0xB0 2225 bytes