Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc5b0a563306b510…

MALICIOUS

PDF

37.7 KB
MD5: bd1c32c3a30c97acd49646c8c5b2b5fb SHA-1: 662630e4703ac4d960c86462f8bc4b0260eba166 SHA-256: bc5b0a563306b510f791cfc040d349fd343af1cd898cb72de562012088f3c24c
124 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file exhibits multiple indicators of malicious activity, including embedded JavaScript and Flash content, and a high ML classifier score. The presence of a JavaScript stream and embedded SWF file suggests an attempt to execute arbitrary code or exploit vulnerabilities. The ML classifier output of 0.999988 strongly indicates malicious intent. The extracted JavaScript file, 'javascript_obj0006_000.js', is a key artifact that likely contains the malicious payload or exploit code.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Adobe.swf
ce5f7936cf8e3536a88a804ce2d6902022df1794fa878bdc64a26866e34ba989
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0xAB5 55839 bytes
javascript_obj0006_000.js
e9afcf4d1d6c5758c2c01a60f802fdab3e036dbc273640cab59d3424e207d405
pdf-javascript-stream PDF /JS object 6 at offset 0xF5 1546 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).