Malicious RTF — malware analysis report

Static analysis result for SHA-256 e75dc39789d3c249…

MALICIOUS

RTF

58.1 KB First seen: 2023-08-04
MD5: 84fc75d62738624137845bd3c180ebe6 SHA-1: abd5d37769d16a7dcd7fc318cb749b4c8685f79b SHA-256: e75dc39789d3c249b58efe4ba0c25b9087d4c693a082ad8c5ecc4119ea4dbfd6
160 Risk Score

Malware Insights

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

The sample is an RTF file containing an embedded OLE object, specifically identified as an Equation Editor exploit. The presence of the 'SE_ENABLE_LURE' heuristic indicates the document prompts the user to enable editing, which would activate the embedded object. This strongly suggests an attempt to exploit a known vulnerability via a malicious document, likely leading to further payload 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_off00003157.bin
70a3e1233ca85c88c6e0e780c645741fcd4d5850d5c043e5cbbfb4ec96ac4622
rtf-objdata-decoded RTF \objdata at offset 0x3157 1992 bytes