Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb1135e2c041f498…

MALICIOUS

PDF

11.7 KB
MD5: f144c5732dbc9ce0977053bfe72ad524 SHA-1: fc12cf769eeaf653aa21b02d15ac9892ae60aad7 SHA-256: cb1135e2c041f49830ca432f175a5debc2ae6c56b4ae6c3b26f0a760385a6a84
146 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). This exploit is designed to execute arbitrary code, as indicated by the critical heuristic firings and the detection by ClamAV as Pdf.Exploit.Agent-36079. The JavaScript is heavily obfuscated, but the core functionality appears to be the exploitation of this known PDF vulnerability to achieve code execution.

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
90a71a5fc1e4591e2767952cdfb64fbeb9310b798d2cf227157819e1520c29dc
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12205 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
c8b39669cbd1759e0df14f95ce0a62de865fb1f3c6e84e7dfb94ae710724b31e
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 5028 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).