Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5d5c963179068a42…

MALICIOUS

RTF / .DOC

2.17 MB
MD5: 9ef78ab16cf7afe0847babcdcd4743ce SHA-1: ba4722e9049c89f221e4b70f7a90d0bdc11e7108 SHA-256: 5d5c963179068a42cf75bebcce58e22912871e84085522de3b5752d0e031d016
180 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that exploits CVE-2017-11882, a known vulnerability in Microsoft Equation Editor. The presence of ".objupdate" and the decoded object class "Equation.3" strongly indicate this exploit is active. The embedded object likely serves as a dropper for a secondary payload, though the exact nature of that payload could not be determined from the provided evidence.

Heuristics 5

  • 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.
  • 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_off000011e1.bin
9aa1c994b2a2fe66d92e425ae31d045a48ecd68f26c7ef7adc306774b482d2ec		 rtf-objdata-decoded RTF \objdata at offset 0x11E1 28919 bytes
objdata_01_off00019b4d.bin
e7360513b374e8393bd4c4b28adef7bcaf4b4715376d4f2c5515615499218833		 rtf-objdata-decoded RTF \objdata at offset 0x19B4D 550268 bytes

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