Malicious PDF — malware analysis report

Static analysis result for SHA-256 b12bdd58e2a9cf12…

MALICIOUS

PDF

11.6 KB
MD5: 80e6f1fe2123d0c2316f4d9c4d84d650 SHA-1: 3095ee6518ee064097c01b66a694eba4881d7cd9 SHA-256: b12bdd58e2a9cf12aa338782765b952adc33c0aa84faed95f7f98a0295618a57
146 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment

The file is a PDF containing embedded JavaScript, which is a common delivery mechanism for exploits. Heuristics indicate the use of CVE-2007-5659, a known PDF vulnerability, and ClamAV detected it as Pdf.Exploit.Agent-36079. The embedded JavaScript is heavily obfuscated but appears to be designed to download and execute a second-stage payload, as suggested by the 'deobfuscated-js' artifacts. The primary attack vector is likely a user opening a malicious PDF attachment.

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
d3ffa8d2d01dcb6a15ec421cdfa3cabbb9aa725ad9616d2ef9dc0b0494f39dbd
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 12246 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
e2160d95cd5345d1ad817641d178797339e44989743c3c70b806c9d465facd59
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 5019 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).