Malicious RTF — malware analysis report

Static analysis result for SHA-256 d23bb6f7fac3436a…

MALICIOUS

RTF

81.8 KB First seen: 2024-08-02
MD5: 0a052f8d7d1dd625c750fe579d2c610c SHA-1: 547181a297641e736ea89b8ac75635dc7186f875 SHA-256: d23bb6f7fac3436a05cbf37fc9daa15ab6d24c9a570a77cc338768786abb21ba
120 Risk Score

Malware Insights

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

The sample is an RTF document containing OLE object data and specifically triggers heuristics for the Equation Editor vulnerability (CVE-2017-11882). The ".objupdate" heuristic indicates that the embedded OLE object is designed to be activated automatically upon opening the document. This exploit allows for arbitrary code execution, which is typically used to download and execute a second-stage payload.

Heuristics 3

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001028.bin
a48d3e1992794d566ced6f8238029a1ecc6f23ed7048864dd441a56d7dccc469		 rtf-objdata-decoded RTF \objdata at offset 0x1028 1719 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.