Malicious RTF — malware analysis report

Static analysis result for SHA-256 c869b11b085ccbde…

MALICIOUS

RTF

4.0 KB First seen: 2024-12-13
MD5: 26aa30505d8358ebeb5ee15aecb1cbb0 SHA-1: 07b82b4c566d5b887f8e9c4966887b378e4dc29e SHA-256: c869b11b085ccbde029c20615c8182fe49fae04244de2a888284eb4763e2561c
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF file contains embedded OLE object data and specifically triggers heuristics for the Equation Editor vulnerability (RTF_EQUATION_EDITOR). The ".objupdate" directive forces OLE object activation, indicating an attempt to exploit this vulnerability for code execution. The embedded data, though truncated, contains strings that appear to be part of shellcode or a payload, including references to 'cer' and potentially PowerShell commands.

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 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_off00000048.bin
1301ea2802adc66ac78135236c54d04dc07877fa55252c73241ae71ed2be9724
rtf-objdata-decoded RTF \objdata at offset 0x48 1823 bytes
objdata_01_off000000b7.bin
1c573fd543e57721fee4e8f9663a19b58590701af0c036febc3297a5e4193472
rtf-objdata-decoded RTF \objdata at offset 0xB7 47 bytes