Malicious RTF — malware analysis report

Static analysis result for SHA-256 6d7db322185b19a4…

MALICIOUS

RTF

1.56 MB Authoring application: Riched20 6.3.9600 First seen: 2018-06-19
MD5: 04e0133a535999b604743eff5b953df1 SHA-1: 606a4097ffbd4035279cf05092977f15d910a4a0 SHA-256: 6d7db322185b19a4b6aa314eb5bff8e232b067596f8847fca5233fc1da01506f
460 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains multiple indicators of exploitation, most critically the CVE-2017-11882 heuristic firing, which points to the Equation Editor vulnerability. The presence of embedded OLE objects and large hex-encoded data blocks further suggests the file is designed to deliver a malicious payload. ClamAV also detected this file as Rtf.Exploit.CVE_2017_11882-6584355-1.

Heuristics 11

  • Equation Editor CLSID critical CVE likely RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
  • ClamAV: Rtf.Exploit.CVE_2017_11882-6584355-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_11882-6584355-1
  • PE header (with DOS stub) in hex data critical RTF_MZ_HEX
    Hex-encoded PE (MZ + DOS stub) found inside RTF — likely an embedded executable payload
  • \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.
  • Package object class high RTF_OBJCLASS_PACKAGE
    OLE Package object — can wrap arbitrary files
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1622KB of hex-encoded data inside \objdata sections — may hide a payload
  • Suspicious extracted artifact high 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.
  • OLE object data medium RTF_OBJDATA
    RTF contains 3 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • OlePres presentation stream in RTF OLE object medium RTF_OLEPRES_STREAM
    RTF contains an embedded OLE object with an OlePres presentation stream. OlePres is an OLE presentation marker and is not enough on its own to identify CVE-2025-21298.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000ef.bin rtf-objdata-decoded RTF \objdata at offset 0xEF 811239 bytes
SHA-256: aaf2d6e06a5fe8f8ef8207fa9e1c42fc567ec6a6d11caeb296409815f32d56ab
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.50, consistent with packed or encrypted content.
objdata_01_off0018c30c.bin rtf-objdata-decoded RTF \objdata at offset 0x18C30C 3980 bytes
SHA-256: 8c4a98e57b3df0a1b0105bf89dc2eed869c578be796a927d39c98969dfa4b4bb
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmd.exe /c%tmp%\vmplay.exe &��D$,f-Q���%
objdata_02_off0018e552.bin rtf-objdata-decoded RTF \objdata at offset 0x18E552 3546 bytes
SHA-256: 275193bcd9c466d4bc2fa20f98e8597530d191a05c2fb4d90c0e4e553d287bcd
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmd.exe /c%tmp%\vmplay.exe A C