Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a6841038d42b01d…

MALICIOUS

PDF

11.8 KB
MD5: 8a8de0a04c59481ad8adbee81ba0afec SHA-1: 73909fe197e08432f221e01fe34b9577ee575fa6 SHA-256: 8a6841038d42b01deac22d88540845c2921609321bac713388b13dc3cb4a7961
146 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, which is flagged as malicious by ClamAV (Pdf.Exploit.Agent-36079). The critical heuristic CVE_2007_5659 indicates the exploitation of a known PDF vulnerability using JavaScript that decodes strings and executes them. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js', are large and obfuscated, suggesting they are designed to download and execute a second-stage payload. The document body is unreadable, providing no contextual clues.

Heuristics 6

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36079 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36079
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
ef8bdac794684ae9cd4eb7091d80e1c5ca478c06c639d72d01626c1f7ce78b6d
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 578 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
d03489a6f417fdd26d687183e01cf8d0bdc48e2a4e2abb2bfad128c10b7e064e
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12177 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
68c958e1798dd7048b8ddf0ac64925702981e1a69372a2c72912665d35d1d4ed
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 4986 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).