Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a9e97eccd4c69c03…

MALICIOUS

RTF / .DOC

40.5 KB First seen: 2023-07-17
MD5: 96f5fd156f0ebdb65baf34ddb24d6c18 SHA-1: d6b2905f8b4417a288850d818e7606ec0429b0ee SHA-256: a9e97eccd4c69c03313c425a6713103bbe256c4d888b02f6d4b2a46d090504b7
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object, specifically targeting the Equation Editor, and uses an \objupdate directive to force its activation. The document body includes a lure instructing the user to 'Enable editing' to view the content, which is a common tactic for macro-based malware droppers. The presence of the Equation Editor exploit suggests an attempt to achieve remote code execution.

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_off00005542.bin
e5070fd224886a35c69c546023c51a9fed1b902df93f5e5bac32a05e37c24dcf
rtf-objdata-decoded RTF \objdata at offset 0x5542 1591 bytes