Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba70ca1665fed153…

MALICIOUS

PDF

11.9 KB
MD5: b404139f16ea17a6c2f2035c10dc9843 SHA-1: 18762e4748b60b18f6ea6f2d44f4744dc412bfad SHA-256: ba70ca1665fed153a5256a393db7f7ec44806e47ffb7efe61573aa004acc2a97
146 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/JScript T1204.002 Malicious File

The PDF file contains embedded JavaScript, specifically leveraging the CVE-2007-5659 vulnerability through the Collab.collectEmailInfo function. This indicates an attempt to exploit a known PDF reader flaw. The embedded JavaScript is heavily obfuscated but the heuristics suggest it is designed to download and execute a second-stage payload. 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
3bfd96291cf5bedeeeac446fd01e59c63043b722da69411ca0df05dbebbcc8b9
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12399 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
ce13d366a6c7b4f8564a56efda3ce46966bc8d1d421740bb4ac7f52cd005b9af
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 5072 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).