Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 62d0b4c65b136264…

MALICIOUS

RTF / .DOC

21.4 KB
MD5: c0cdde350fd3c1e7e1c4ccb723d741b9 SHA-1: e329dc867d11ec593addf9afa2a1ca48b9526243 SHA-256: 62d0b4c65b13626421d99d674713e7c7127a4c0ad6cad0ed6d7c4f2b0af748ed
180 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects, specifically triggering the CVE-2017-11882 vulnerability through the Equation Editor. This exploit is designed to execute arbitrary code, likely leading to the download and execution of a secondary payload. The presence of the 'EQUatIOn.3' class name is a strong indicator of this specific exploit.

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.
  • Decoded Equation Editor payload + PE critical RTF_EQUATION_EDITOR
    RTF decodes to an Equation Editor ProgID adjacent to OLE activation and the same decoded object stream contains embedded PE bytes. This matches the Equation Editor exploit surface used by CVE-2017-11882 / CVE-2018-0802 documents, while requiring payload evidence to avoid flagging benign Equation references.
  • \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_off00000f39.bin
14e38ed4a00a828bf2d8f2f5ba7951cf846e4dd56fb254116c5263af53fe0f33
rtf-objdata-decoded RTF \objdata at offset 0xF39 1788 bytes