Malicious PDF — malware analysis report

Static analysis result for SHA-256 e978131319fd9e4e…

MALICIOUS

PDF

11.5 KB
MD5: 7d6c95febf61372e6434ddd158e0ada7 SHA-1: 4c62860ff70d037b4d3614b5b0ce6cbd8a478a26 SHA-256: e978131319fd9e4ec63f9b674453a60d4a38bf9777ae4a2bfdff9829c63afcf2
146 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, which is flagged as malicious by ClamAV (Pdf.Exploit.Agent-36079). Critical heuristics indicate the use of CVE-2007-5659, a known vulnerability related to JavaScript execution in PDF documents. The embedded JavaScript is heavily obfuscated but appears to be designed to download and execute a secondary payload, as suggested by the presence of multiple deobfuscated JavaScript files and the 'PDF_JAVASCRIPT' heuristic.

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
0cb048864ab3aa64f604f0bc3dab8f159f5bd8ff60a6f134c2cfd3123a4aadd2
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12037 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
fc0550c9dee31a27abef2008424952118ce0c4a96dbb31808072e106bc5ac8a4
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 4942 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).