Malicious RTF — malware analysis report

Static analysis result for SHA-256 e2ea24017d1e6026…

MALICIOUS

RTF

37.2 KB First seen: 2023-07-12
MD5: f351161a0fbeea7aede8237afb6e9b1f SHA-1: 245961f753204245461c7885ab72f24edfae986f SHA-256: e2ea24017d1e602649ea496804e65442a4e1690e3b7ff779f4cd888edd75d09c
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.005 Visual Basic

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, a known exploit vector. The document also contains a lure instructing the user to 'Enable editing', indicating a social engineering attempt to bypass macro security. The embedded OLE object is automatically linked and updated, suggesting it is intended to trigger an exploit upon opening.

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.
  • 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
  • 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_off00004470.bin
32d1d492c930fac04141bab4391ff459b0e5803f829fae9fcc6abfb18f4b655b
rtf-objdata-decoded RTF \objdata at offset 0x4470 1676 bytes