Malicious PDF — malware analysis report

Static analysis result for SHA-256 bafd4ab73cd06b88…

MALICIOUS

PDF

28.9 KB Created: 2011-72-51 03:25:00 Authoring application: String.fromCharCode
MD5: efdfa180904243281b049e815bc008ac SHA-1: c327ab190d674790c1c4b4b98989df611e52c521 SHA-256: bafd4ab73cd06b8828821251354a9cfab8e07926d09895396ec0705088a3ccbe
308 Risk Score

Malware Insights

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

The PDF document leverages multiple critical vulnerabilities (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through JavaScript embedded in its metadata. This JavaScript stager is designed to execute arbitrary code, likely to download and run a second-stage payload. The use of String.fromCharCode and obfuscated JavaScript further indicates malicious intent.

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
15ac52c7ae544782cf18923310d738a2dc300590b630509100c144aa81447f2f
pdf-javascript-stream PDF /JS object 1 at offset 0x7136 394 bytes
info_arithmetic_stage_000.js
6f6da598c3ca7f91ca4221074eb15cd230866b6309c97944315f5149bd495144
deobfuscated-js PDF /Info Title arithmetic JavaScript at offset 0x23 3654 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).