Malicious PDF — malware analysis report

Static analysis result for SHA-256 a110ebcd5760a5ec…

MALICIOUS

PDF

21.2 KB Created: 2012-09-17 23:33:20 +04:00 Authoring application: Adobe Acrobat 10.0 (via Acrobat Web Capture 10.0)
MD5: fabdc71ac8d6a8e523dc581516a9e769 SHA-1: ede524222112c98158c3ef40be60bfe7afa20d02 SHA-256: a110ebcd5760a5ec4be734e604c7af9d7dde1053ed0d0a1b34e6820f7a2c4045
366 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF file contains embedded JavaScript that is heavily obfuscated using a base-31 encoding and string concatenation techniques. Critical heuristics indicate the exploitation of multiple CVEs related to JavaScript execution within Adobe Reader, specifically CVE-2009-4324 (media.newPlayer), CVE-2009-0927 (Collab.getIcon), CVE-2007-5659 (Collab.collectEmailInfo), and CVE-2008-2992 (util.printf). The ClamAV detection of 'Pdf.Exploit.CoolExploitKit-6308636-0' further confirms its malicious nature. The script's primary function appears to be downloading and executing a second-stage payload, leveraging the identified vulnerabilities.

Heuristics 11

  • 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: Pdf.Exploit.CoolExploitKit-6308636-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.CoolExploitKit-6308636-0
  • Base-N pair JavaScript stager high PDF_BASE_N_PAIR_JS_STAGER
    PDF JavaScript stores a long payload as character pairs decoded with parseInt(radix) and String.fromCharCode, then evals the result. The decoder only handles bounded pair tables and only fires when the recovered stage contains 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0019_000.js
f54708f6b958285ecf903c2870cd9ed42ff909892c9b30e6992828d80b463fc4		 pdf-javascript-stream PDF /JS object 19 at offset 0x487 9426 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 5 long base64-like blob(s).
base_n_pair_stage_000.js
360d04712a398620ed05df99526ce6851fbd48a46be49231ea2b0b4756c26917		 deobfuscated-js base-31 pair decoded JavaScript at offset 0x495 4197 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).
icc_00_off00003018.icc
653b586c4707574ffcd648ba35494daed2c76ceafcf4c07d315ed961b1dc347f		 pdf-icc-profile PDF ICC profile at offset 0x3018 408 bytes
icc_01_off000032b3.icc
2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e		 pdf-icc-profile PDF ICC profile at offset 0x32B3 3144 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.