Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 97c51279420acfe3…

MALICIOUS

RTF / .DOC

12.2 KB
MD5: f5791fcd71c9e28a1348a8035e793e05 SHA-1: 6e0bc43747470108d78949726832a9d2d9a22470 SHA-256: 97c51279420acfe33996375c38ebcc042b31d3d7924f5892a92bd766501b35a5
120 Risk Score

Malware Insights

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

The sample is an RTF document that leverages the Equation Editor vulnerability (CVE-2017-11882) to execute arbitrary code. The presence of \objdata and \objupdate directives strongly indicates the exploitation of OLE object handling within RTF. This technique is commonly used to download and execute a second-stage payload, leading to a malicious infection.

Heuristics 3

  • 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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001e1e.bin
624c641e10e5fff0b06ae1891c3f5bfb31f6991e2d5de406dd5964bd4c3721a4
rtf-objdata-decoded RTF \objdata at offset 0x1E1E 1745 bytes