Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6db51f3e22fca778…

MALICIOUS

RTF / .DOC

12.4 KB
MD5: 946c27b4a0708adba784f8d30ef2a7e2 SHA-1: 0cb1af4e8f3fc5a04b01cad764b25c7805172ccf SHA-256: 6db51f3e22fca7788fc651d8d6451cd4ed3f5e67f043a06286b4938b02f82971
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is an RTF document containing embedded OLE objects, specifically triggering heuristics related to Microsoft Equation Editor and CVE-2017-11882. This indicates the document is designed to exploit this vulnerability for code execution. The presence of ".objupdate" and ".objdata" sections further supports the exploitation of embedded objects. The lack of document body text or scripts means the exact payload cannot be determined, but the exploitation method is clear.

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.
  • \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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000b3a.bin
5fcbf58bb482ce25ad1237131e270e0b562f9992bc081881b7b6ffec60756f6f		 rtf-objdata-decoded RTF \objdata at offset 0xB3A 1508 bytes

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