Malicious PDF — malware analysis report

Static analysis result for SHA-256 3aa9cd6a6c69af4f…

MALICIOUS

PDF

6.7 KB
MD5: 480ee4c457bef710473cceb7810810a2 SHA-1: 31aaed2032418276dfa133962ff1f3cc1e9ded04 SHA-256: 3aa9cd6a6c69af4fb2ad68458f3f33c85549aad65796c6fafcb6b3206717f156
266 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 CVE-2009-4324, CVE-2009-0927, and CVE-2007-5659 through embedded and obfuscated JavaScript. The extracted artifact was detected by ClamAV as Js.Exploit.Shellcode-18. The JavaScript appears to be designed to download and execute a second-stage payload, though the exact mechanism is obscured.

Heuristics 8

  • 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)
  • 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.
  • 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_obj0039_000.js
e8882887ddc5381b2b84226dff8f0a5f86af796ec8d1d57a6674dd6b32c88763
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 21457 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
120d086d0b76d7e18b4806f4b762b312618aad12b1f2f30254bf572fb1708769
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5416 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
8e76b89962a3ff1175434556061a1f846e3fe1c67c8a2b2bd1d1bb8cf58a4001
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5416 bytes