Malicious RTF — malware analysis report

Static analysis result for SHA-256 82c3bfeff5bb9632…

MALICIOUS

RTF

32.7 KB First seen: 2023-07-13
MD5: 1e7180f17652e02901365aee4e73661a SHA-1: baddeb931dc76948da53575a182369780b12ca35 SHA-256: 82c3bfeff5bb963269a9c346f269eeb4ea0f434b2b341ad6470efca7cd8ed71a
160 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object and specifically triggers heuristics related to Equation Editor exploitation and OLE activation. The document body includes a lure instructing the user to 'Enable editing', which is a common tactic to bypass security measures and execute embedded exploits. The presence of these indicators strongly suggests an attempt to exploit a vulnerability, likely via the Equation Editor, to gain initial access.

Heuristics 5

  • 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 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00004963.bin
184fb5a2d3b4dcf99d6aaefc032564d09c59dedf578ec778e1099c3016c5c4f2
rtf-objdata-decoded RTF \objdata at offset 0x4963 1164 bytes