Malicious PDF — malware analysis report

Static analysis result for SHA-256 c299aeaf63a5e6ff…

MALICIOUS

PDF

15.7 KB
MD5: 45a32ce83a927087cca945c449c7a76b SHA-1: 6153f8463abc5ad33d1e06c921846ba24f06be26 SHA-256: c299aeaf63a5e6ffda17f9fe43f2c050b24422e376f24497cb48e5f1f9f5caef
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a large comment-padded eval stager. This JavaScript is designed to execute arbitrary code, as indicated by the eval() call and String.fromCharCode usage. The ClamAV detection 'Pdf.Exploit.Agent-36086' strongly suggests this is a known exploit. The primary attack pattern involves leveraging a PDF vulnerability to run malicious scripts, likely for downloading and executing further stages.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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.
  • 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
javascript_obj0006_000.js
f9279c2925201fecf0b4ebeb2c155197d56d61f95036e37bb1f19c22c56db901
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425033 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).
legacy_pdfkit_stage_000.js
597509254d755b9e8b611a97b738f82be775a6f09c8bc07bffeb5ba25e32a7b5
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262144 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 640 long base64-like blob(s).