Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 9c1014d8c296749e…

MALICIOUS

RTF / .DOC

40.5 KB First seen: 2023-02-21
MD5: 5b657208245ba354da2a90ad6bc02cf6 SHA-1: 1a34ca79f7cfaf59354026117c1053865ce0960a SHA-256: 9c1014d8c296749e1442ecd5c7585d730db9bcaeb0cc99bd44071b784954cce4
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 split Equation Editor ProgID, a known exploit technique. The \objupdate directive forces OLE activation, and the document body includes a lure to 'Enable editing' to bypass security measures. This combination strongly suggests an attempt to exploit a vulnerability, likely for initial access.

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_off00005518.bin
62ac0ccaa877552736de7e30104211de3186b4c000dd85e43875eef93440b3d7
rtf-objdata-decoded RTF \objdata at offset 0x5518 1479 bytes