Malicious RTF — malware analysis report

Static analysis result for SHA-256 2fe4170ed264815f…

MALICIOUS

RTF

31.7 KB First seen: 2023-07-05
MD5: eda69f7aa485bc2603035654f6483a50 SHA-1: 363663f56db101783bcd94967d33c22bdab6ede8 SHA-256: 2fe4170ed264815f95759a1eff2f4b8ee0977b1a1e7e473d71909608c98181f3
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.005 Visual Basic

The sample is an RTF document containing an embedded OLE object that exploits the Equation Editor vulnerability (CVE-2017-11882). The presence of \objupdate and SE_ENABLE_LURE heuristics indicates that the document is designed to trick the user into enabling content, which then triggers the exploit. The primary goal is likely to download and execute a second-stage payload.

Heuristics 5

  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off00005b2b.bin
66d1c87d02a3ee132d69a93913ea8fd48465fe229354ea462b6620a9a5c70c43
rtf-objdata-decoded RTF \objdata at offset 0x5B2B 1508 bytes