Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9fab30df458d2bd…

MALICIOUS

PDF

25.6 KB Created: 2011-72-51 03:25:00
MD5: c22587ef62379b44f8182380787b55a6 SHA-1: be793605164dd107e9eff7f5040bb31d780b5e2b SHA-256: a9fab30df458d2bd3651ef6d46fc921dc8a01d7f186e0749388d6f5c948cf90e
306 Risk Score

Malware Insights

MITRE ATT&CK
T1204.001 Malicious Link T1059.001 PowerShell T1059.003 Windows Command Shell T1059.007 JavaScript

This PDF file contains embedded JavaScript that leverages multiple critical Adobe Reader vulnerabilities including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript stager, recovered as info_arithmetic_stage_000.js, is designed to exploit these flaws, likely to download and execute a second-stage payload. The use of arithmetic operations within the PDF metadata to construct JavaScript further indicates a deliberate obfuscation technique to evade detection.

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)
  • PDF metadata arithmetic JavaScript stager high PDF_INFO_ARITHMETIC_JS_STAGER
    PDF metadata hides JavaScript as arithmetic character-code tokens inside document information fields, then a launcher rebuilds it with String.fromCharCode and eval. The decoder is gated on metadata access from the launcher, a large arithmetic token table, and recovered exploit-like JavaScript.
  • 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.
  • 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_obj0001_000.js
18b749dffecd9694524fb501376aac43fc7cc746a344d3514f537cb16cb9837a
pdf-javascript-stream PDF /JS object 1 at offset 0x63C6 508 bytes
info_arithmetic_stage_000.js
28856845e6b18bb985aecc63fd6af09f4f8ce3e052876ef4395edbfd8f00673a
deobfuscated-js PDF /Info Producer arithmetic JavaScript at offset 0x23 3722 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).