Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 b322682150da97f4…

MALICIOUS

RTF / .DOC

34.4 KB First seen: 2023-05-26
MD5: 0f0a33edc463ad271153abcf0cfe968c SHA-1: 148d18f49f9bca15e6d5458dba5ae7f7c8f40dd8 SHA-256: b322682150da97f483ed8b6ba577f31d85e7a71161172265a55dd41c2619526c
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with a specific Equation Editor ProgID, and uses an \objupdate directive to force activation. The document body includes a lure instructing the user to 'Enable editing' to view the content. This combination strongly suggests an exploit targeting the Equation Editor vulnerability to execute a malicious payload.

Heuristics 4

  • 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
  • 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_off00004248.bin
2a395a57c4629a656194162d97c5b1a86aa451ac7ee4d608fc4594a9bf1fac3e
rtf-objdata-decoded RTF \objdata at offset 0x4248 1703 bytes