Malicious PDF — malware analysis report

Static analysis result for SHA-256 26eb13ba68efa024…

MALICIOUS

PDF

9.3 KB
MD5: 17ef535a0f430218872eded719d334e2 SHA-1: 89d99d0a99e0b5c3dae11ee03acaf508ebf15a6b SHA-256: 26eb13ba68efa0249d8de28744157a894c37370fe6c825bf3672d6269364b9be
208 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability, specifically using the Collab.collectEmailInfo method. This technique is commonly used to download and execute a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple deobfuscated JavaScript files further supports the conclusion that this PDF is designed to exploit the reader.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • 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
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 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
81999f5d137bedeb151ffc18a5596d216f141741746e3380c408bd75d398988b
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 11895 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
d93878ca50349607d5ef5554364d6908295ab8d31463c7215d4c72df88ba5db5
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 4965 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).