Malicious RTF — malware analysis report

Static analysis result for SHA-256 a31854363fb1f8b2…

MALICIOUS

RTF

3.0 KB First seen: 2023-01-16
MD5: 223bfb0ccdf5be96ed1108e84c76eaa1 SHA-1: 9053104e8b48448b3e473379d5059c885ff141f4 SHA-256: a31854363fb1f8b282c2f953f5b6eb58ce8476e53e6ad2cb9b5fb0b451a7ac44
200 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object specifically related to Equation Editor, triggering heuristics for CVE-2017-11882. This indicates the file is designed to exploit this known vulnerability, likely through user interaction with the embedded object, to achieve arbitrary code execution.

Heuristics 5

  • Obfuscated Equation Editor ProgID + activation critical CVE related RTF_EQUATION_EDITOR
    RTF decodes to an Equation.3 ProgID from top-level \objdata hex after nested RTF junk groups are ignored, and the document also contains \objemb plus \objupdate activation. This is an obfuscated Equation Editor exploit surface associated with CVE-2017-11882 / CVE-2018-0802 families, but no exact malformed MTEF CVE primitive was recovered from this object.
  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off0000007c.bin
7d62e57a0aff7837806f819f88ded4ce8569b4547cfc8d872e14489137e35c54		 rtf-objdata-decoded RTF \objdata at offset 0x7C 1430 bytes

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