Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c5516155918005c…

MALICIOUS

PDF

767.4 KB
MD5: ed832a8d48ad0ea2d34913aa5c14b0a6 SHA-1: 7fc7704c015078076a5c33d3c0761a5d94bc5de7 SHA-256: 3c5516155918005cccd6ee29255f7f542f37ea2e3b99ca5019c95d8dfca40efa
316 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment T1190 Exploit Public-Facing Application

The PDF contains embedded JavaScript and a Flash object, as indicated by the PDF_JAVASCRIPT, PDF_JS, and PDF_RICHMEDIA heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of an embedded PDF further indicates a multi-stage attack. The primary goal appears to be the execution of malicious code via these embedded components, likely leading to the download and execution of additional malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 9

  • Secondary embedded PDF body has suspicious static findings critical POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • ClamAV: Pdf.Exploit.Agent-35955 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35955
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
zVGWPnPsl.swf
ae13437efad4e3a4f03cb0339d03b7d795966b217d30a540767c4ae26f402285
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0x146D 26774 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35955
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.
javascript_obj0006_000.js
15689f302e582c730e2957af9f693527bed5d4b0c0400330afa9ba85ee307ff3
pdf-javascript-stream PDF /JS object 6 at offset 0x13C 12114 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 10 eval/decoder/string-building token(s). Carved artifact contains 3 long base64-like blob(s).
polyglot_child_pdf_off000b6b76.pdf
1a6680d1fc92463ff3785c6d92ec8a5a6b1798722e1986bd89fadc1455661f33
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0xB6B76 37419 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35955
Obfuscation or payload: unlikely