Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae88ccfb07b41428…

MALICIOUS

PDF

2.0 KB
MD5: c2e19ae8cb205408e900dbc53079c8bc SHA-1: 4f4df070342d87830161147d38745810b2d5c3af SHA-256: ae88ccfb07b41428d4efca5732b1aad55065db17346814d5af8f71fdeb767fc1
226 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes eval() and unescape() functions, indicating obfuscation. The critical CVE-2007-5659 heuristic firing points to the exploitation of a known vulnerability via the Collab.collectEmailInfo method. This JavaScript is likely designed to download and execute a second-stage payload, as suggested by the ClamAV detection as a dropper.

Heuristics 8

  • 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.Dropper.Agent-7292981-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7292981-0
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
433d6141b5fc932a52d94051061c1f7566cbde37bb51ce636d76e20ed4ab2bf6
pdf-javascript-stream PDF /JS object 111611 at offset 0x6D5 297 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
8fca8720a614c7e6659a3b0ad06e141467e0d5e2884a3b15b0411f717aa8ad9a
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2640 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).