Malicious RTF — malware analysis report

Static analysis result for SHA-256 bd32a9cbb3ed1a61…

MALICIOUS

RTF

49.1 KB First seen: 2023-07-20
MD5: e96ec153a057e316705a5ac7c432636b SHA-1: 858e826c3d6c8ef66b0713d84353572606a59d87 SHA-256: bd32a9cbb3ed1a616bf91d7121386a78cf6bb2b8c904088d1daa3982edb4fb8b
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object specifically identified as being related to Equation Editor, a known vector for exploits. The presence of \objupdate and SE_ENABLE_LURE heuristics indicates the document is designed to trick the user into activating the object, likely to trigger an exploit. No scripts were extracted, and the document body content appears benign, suggesting the malicious payload is entirely within the embedded object.

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_off0000596b.bin
c4f613aaba3c2482bda8eb5435ea1a1c8692b378e6998e37bd2ea09f82789f5a
rtf-objdata-decoded RTF \objdata at offset 0x596B 2035 bytes