Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdc4486e6bd7dc29…

MALICIOUS

PDF

11.7 KB
MD5: 67b26f7db17ab383717ecc271df6bc0d SHA-1: fade8035f4d29ad23729bad41c6b642a1765b913 SHA-256: fdc4486e6bd7dc29ff9fce598ef6ce8bf1b674c789bb5e8d5fa9499e34ab6d98
146 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

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 vulnerability within the PDF structure to execute this JavaScript. The JavaScript is heavily obfuscated but appears to be designed to download and execute a second-stage payload. The presence of multiple deobfuscated JavaScript files suggests a complex, multi-stage attack.

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
411b1eaa962c8b7a0152ff57f6e0f215c45d4d244f49d65f7ed72c2a4b97675a
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12194 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
407a3d247ffddc9b572059a470e241e6367664cfd42290be4f9fd937e9f1b078
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 4963 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).