Malicious PDF — malware analysis report

Static analysis result for SHA-256 581e07ac48671b30…

MALICIOUS

PDF

37.7 KB
MD5: f731458bb10fe3343bbbeffc0804fa9a SHA-1: cc534fa6ca0bee3952c889e5b4211a4b994feca1 SHA-256: 581e07ac48671b307abc8ed26dbeace6425b8152160d3987ebff4a2d970d4e27
124 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1566.001 Spearphishing Attachment

The PDF file exhibits multiple indicators of malicious activity, including embedded JavaScript and Flash content. The ML classifier strongly flags this PDF as malicious. The presence of embedded JavaScript, specifically identified as 'javascript_obj0006_000.js', suggests an attempt to execute code. The combination of these elements points towards a likely exploit delivery mechanism or a downloader for further malicious stages.

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 0xABB 55839 bytes
javascript_obj0006_000.js
be315aa740ab7e1926afb7c0ff43307757b17d1377e77c3c488a31b00c33321a
pdf-javascript-stream PDF /JS object 6 at offset 0xF5 1558 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).