Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba3e0003b61cbe43…

MALICIOUS

PDF

28.5 KB Created: 2011-72-51 03:25:00 Authoring application: String.fromCharCode
MD5: de6bfa00e706d26663268ba95c692ec2 SHA-1: 155d2a22c760361e5cc96181eaf22f2cf73e6b89 SHA-256: ba3e0003b61cbe43fb837480731cb237b98e17d312ab59dc48dfc8b727586e56
266 Risk Score

Malware Insights

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

The PDF file contains multiple critical heuristic firings indicating exploitation of CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. These vulnerabilities are leveraged through embedded JavaScript, which is further indicated by the 'PDF_JAVASCRIPT' and 'PDF_JS' firings. The 'legacy_pdfkit_stage_000.js' file suggests a deobfuscated JavaScript payload. The script's likely intent is to download and execute a second-stage payload, exploiting the identified PDF vulnerabilities. The 'String.fromCharCode' usage also points to obfuscation techniques commonly used in PDF-based malware.

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)
  • 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)
  • 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
4b11bb701598b2c6f17184a7ab7c0503b35d59f30796a3ad1cda786535fdcfa4
pdf-javascript-stream PDF /JS object 1 at offset 0x6FC4 381 bytes
legacy_pdfkit_stage_000.js
26954ffa657de3feb894571f69c6af1726502753747cced267d25931058abb51
deobfuscated-js metadata float-expression decoded JavaScript at offset 0x91 3636 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).