Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 24ea98fa4d2fb857…

MALICIOUS

RTF / .DOC

3.6 KB
MD5: 0701436bb925fa0597f03c5b4ce93c3f SHA-1: 541b0f40c570a7add87fa46f02e325a7af2829b4 SHA-256: 24ea98fa4d2fb857ba478bf7f909b9df1847ed1e2440179cb828a0b0be8c0514
180 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that exploits the Equation Editor vulnerability (CVE-2017-11882). This vulnerability allows for the execution of arbitrary code upon opening the document. No document body text or scripts were extracted, but the presence of the Equation Editor exploit strongly indicates a malicious intent to compromise the user's system.

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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000084.bin
9f7efe817da1321ec3e8fe3df76743e1bb55e89a0b582b4ea5a298a44f792954
rtf-objdata-decoded RTF \objdata at offset 0x84 1680 bytes