Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ed6e05001f2102cb…

MALICIOUS

RTF / .DOC

38.0 KB First seen: 2023-04-20
MD5: f03b5c3a2cb99f15efff619325bca711 SHA-1: d18f99cca5a93026b1b51d6ac98a9e2618c08d20 SHA-256: ed6e05001f2102cbcffe2dddfba91ec120bc95840150ed781e3572b9cb594666
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, and the ".objupdate" directive forces OLE activation. The document body contains a lure instructing the user to 'Enable editing', which is a common technique to bypass macro security settings and trigger the exploit. The presence of these elements strongly suggests an attempt to exploit a vulnerability, likely related to the Equation Editor, 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_off0000408a.bin
67221810d9f3019165a18f9ebaeb49c6240d8a2ea817351486f62f2bb09e54fd
rtf-objdata-decoded RTF \objdata at offset 0x408A 1641 bytes