Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a34740227c90d75…

MALICIOUS

PDF

11.9 KB
MD5: 9cc2a3296a485559dfbb889110b373cf SHA-1: a27a4f07dc5b5c50132776ca08dbf48ce30360d4 SHA-256: 9a34740227c90d75ca28fd0dcfe114c9b428b8652087245f9468920c03dbc2b7
146 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the `collab.collectEmailInfo` function. This JavaScript is obfuscated and likely designed to download and execute a second-stage payload. The presence of multiple JavaScript streams and the ClamAV detection as 'Pdf.Exploit.Agent-36079' strongly indicate malicious intent.

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
16b9e61156cdf3898aa09dd26a11bb195a5c046c99cfc31dccff927031c9379d
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12366 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
b19cd2decfa745802f37b309582b0724b9837d2abce8ba96b8b5907547c1e887
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 5050 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).