Malicious PDF — malware analysis report

Static analysis result for SHA-256 88660579e12ebe79…

MALICIOUS

PDF

11.8 KB
MD5: 665d13c636d9dc61237f369d761a022f SHA-1: db690c5583f076cce859c29fe41ad0b0c80f796c SHA-256: 88660579e12ebe79921b8d95211fe5ec586106a3eceba20f6f5f55ba30fcd975
146 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT' and 'PDF_JS'. The critical 'CVE_2007_5659' firing specifically points to the exploitation of a known vulnerability using JavaScript. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js', are likely responsible for the malicious behavior, potentially downloading and executing further payloads. The ClamAV detection further confirms its malicious nature.

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
5ae3cf36d23bb420d42b73b3b01e6f64686bf04173bcc551069970fa5c62c1d8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12226 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
2ad402cec522be995355e411291e4af70aeb97a25467359859a63ca8cd888a3c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 5056 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).