Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 7e4da069dde7de36…

MALICIOUS

RTF / .DOC

40.2 KB First seen: 2023-04-19
MD5: d1de37a191ab5a2f70c4b6ee589dc55b SHA-1: f158fe6e85e230c455246220b66e1f8c72f6b2db SHA-256: 7e4da069dde7de363aba1aae6bf7989bd4bb2c32dae93410e1f414d1ab35fba8
160 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object and an ".objupdate" directive, indicating an attempt to exploit vulnerabilities related to OLE activation. Specifically, the "RTF_EQUATION_EDITOR" heuristic suggests a likely exploit targeting the Equation Editor component. The document also contains a lure instructing the user to "Enable editing", a common tactic to bypass macro security and trigger the exploit.

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_off000057a4.bin
1a7d94b9a9e67d7654c3e3a75f7749bbcb481a665c7da679ce86186e377b2b52
rtf-objdata-decoded RTF \objdata at offset 0x57A4 1551 bytes