Malicious PDF — malware analysis report

Static analysis result for SHA-256 943cde265fa941bf…

MALICIOUS

PDF

3.0 KB
MD5: 7c58cc77825f0466ab78faa1d825f96a SHA-1: 42f83e190fc13e819a4889ee9ade11ab9474bf4d SHA-256: 943cde265fa941bf9cc4497b5b9b70902ec9dc74c8bad2b612bcce4f815ba1ec
358 Risk Score

Malware Insights

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

The PDF file contains multiple critical heuristic firings indicating the exploitation of several CVEs (CVE_2009_4324, CVE_2009_0927, CVE_2007_5659, CVE_2008_2992) through embedded JavaScript. This JavaScript is further obfuscated and uses eval() to execute. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js', are indicative of a multi-stage attack designed to download and execute a secondary payload. The ClamAV detection of 'Pdf.Exploit.Agent-35646' further supports this assessment.

Heuristics 9

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • 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)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
f347f4dc9304d9f0b78840aba08035410d7d6ce4777a483fe857af9199ae86c4
pdf-javascript-stream PDF /JS object 7 at offset 0xDB 34844 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
a8453d95464ca2795985d5655a7cc2d1534cfd5f9d84bc86e39e05a7e1766f7a
deobfuscated-js split-join delimiter stripped JavaScript at offset 0x108 7508 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35646
Obfuscation or payload: likely
Carved artifact contains 13 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).