Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 caad120ede23cdc1…

MALICIOUS

RTF / .DOC

283.9 KB
MD5: 1899f397d74850fd0997fc141c46e49b SHA-1: 8c201931b40512aff8f91efbe3998c1dca165816 SHA-256: caad120ede23cdc1e2926ca0b491010340115bb8d282cd2b2480ba63af0bd350
182 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF document contains an embedded OLE object that leverages the CVE-2017-11882 vulnerability in Equation Editor. This exploit is designed to drop and execute a secondary payload, likely a Windows executable, as indicated by the high entropy and MZ header found in the decoded OLE object. The file's SHA256 hash is provided as a primary IOC.

Heuristics 5

  • Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED
    RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact 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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001a0b.bin
a70c2efc60dac2274a64dbf741e001cf506e95f1bf87b9b1541cdde74e6ffd3e
rtf-objdata-decoded RTF \objdata at offset 0x1A0B 141858 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.