Malicious RTF — malware analysis report

Static analysis result for SHA-256 1bfd7e3dfa33d09b…

MALICIOUS

RTF

876.3 KB Created: 2018-05-02 20:25:00 First seen: 2019-11-20
MD5: dd509f7b263b4f679ed1531a5f79dd16 SHA-1: 3b9cf62b9a4c5a863da4505daa3122d791070f3e SHA-256: 1bfd7e3dfa33d09bf9e5a5829bfd547b7c31abd923b3e03dd4062a7124ced2fa
262 Risk Score

Malware Insights

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

The RTF file contains multiple embedded OLE objects and triggers an ".objupdate" command, which is indicative of exploiting vulnerabilities like CVE-2017-8759 for client execution. ClamAV detections further confirm its malicious nature, flagging it as Doc.Macro.Obfuscation. The primary attack vector is likely spearphishing attachment, with the embedded OLE object serving as the mechanism to download and execute a secondary payload.

Heuristics 6

  • CVE-2017-8759 — MSXML SAX OLE activation critical CVE likely CVE_2017_8759
    RTF contains a hex-encoded OLE1 object for Msxml2.SAXXMLReader.6.0 followed by an embedded OLE compound document, and the document requests OLE activation. This matches the RTF staging shape used for CVE-2017-8759 SOAP/WSDL parser code injection.
  • ClamAV: Doc.Dropper.Agent-6412232-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-6412232-1
  • \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 12 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://schemas.microsoft.com/office/word/2003/wordml In RTF body

Extracted artifacts 12

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00002c1b.bin rtf-objdata-decoded RTF \objdata at offset 0x2C1B 24123 bytes
SHA-256: d985b81cedd5cf06739a8690205448b4eb12729038c9988da7024a1b0c976ca3
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_01_off000142a5.bin rtf-objdata-decoded RTF \objdata at offset 0x142A5 24123 bytes
SHA-256: 2d576788acbeb31285a865bf0fb8212ed10b1986bd1e12663be93daa404e35de
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_02_off0002592f.bin rtf-objdata-decoded RTF \objdata at offset 0x2592F 24123 bytes
SHA-256: 91025d346091bb94da48ab88812ee8042dfef3d0b30efb70a46f632a43878340
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_03_off00036fb9.bin rtf-objdata-decoded RTF \objdata at offset 0x36FB9 24123 bytes
SHA-256: 30cabe64ea91260c03c43ba02630635f7c8c552e3d43479f60de7b76d2d15000
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_04_off00048643.bin rtf-objdata-decoded RTF \objdata at offset 0x48643 24123 bytes
SHA-256: 9f57cd1544c51c30e2e4bd358cfe84b69e8e12d22c7bab708e71ec2257c481a1
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_05_off00059d19.bin rtf-objdata-decoded RTF \objdata at offset 0x59D19 24123 bytes
SHA-256: 234a295f31611979f71ac6225464bfe50ed8d0f43f2f22994e9984155c3f0965
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_06_off0006b3a3.bin rtf-objdata-decoded RTF \objdata at offset 0x6B3A3 24123 bytes
SHA-256: b81c59dfcbf4444d11476d4bb18ed880682b66e25b8e84faa8c3ea1945eb4644
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_07_off0007ca2d.bin rtf-objdata-decoded RTF \objdata at offset 0x7CA2D 24123 bytes
SHA-256: 8ca51ac37c49a9ff123d3ada75fb1dc31e9fed1f456b98a7529362698790d5df
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_08_off0008e0b7.bin rtf-objdata-decoded RTF \objdata at offset 0x8E0B7 24123 bytes
SHA-256: 54e232fbf4babaf340deb59703cece46482ed7c1091d24dff20287c9fc129731
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_09_off0009f741.bin rtf-objdata-decoded RTF \objdata at offset 0x9F741 24123 bytes
SHA-256: 566ccaaf853a3b76e3d39b1a9e65c063c64099f8404df44f357feaa30be495ef
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_10_off000b0e17.bin rtf-objdata-decoded RTF \objdata at offset 0xB0E17 24123 bytes
SHA-256: f357a46e14fb55a3fe3f0d066795d8188fa240b88de36eb449eb49a3e7563774
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely
objdata_11_off000c24a1.bin rtf-objdata-decoded RTF \objdata at offset 0xC24A1 24123 bytes
SHA-256: 26916214f427fc15db88f055415098cb03d67be7626078e70afd05320a3c4778
Detection
ClamAV: Doc.Dropper.Agent-6412232-1
Obfuscation or payload: unlikely