Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d30aa0b1400fe6da…

MALICIOUS

RTF / .DOC

178.8 KB First seen: 2023-10-26
MD5: fb162f5500ae3564cd03ae1c851cedc7 SHA-1: c9f86f3754c0bec8a6e2c1f1929aeabd0380f8a6 SHA-256: d30aa0b1400fe6da0c7779263580a4db2338376a873baf7a0ef288b580fe8a3c
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically identified as an Equation Editor exploit. The document body provides a lure about financial auditing, instructing the user to 'Enable editing'. The presence of \objdata and \objupdate heuristics indicates the OLE object is designed to be activated, likely leading to the execution of 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_off00002a7a.bin
991bc883bdfd949611a5e17e81a20eacc52d0c601bebdf0102bdf9ea5c2bab96
rtf-objdata-decoded RTF \objdata at offset 0x2A7A 1759 bytes