Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1b8099bb7fb471a…

MALICIOUS

PDF

25.1 KB Created: 2011-72-51 03:25:00
MD5: 51bc8023b90cf6bba77cdc2c163e2564 SHA-1: 0d3265a8cc4ce1503779cf302d49a0f03f04ee08 SHA-256: c1b8099bb7fb471afb78776df6d38de05a2d0c5c615c03c24165b0e598a8c463
396 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1204.002 Malicious File: User Execution: Malicious Attachment T1059.001 Command and Scripting Interpreter: PowerShell T1059.003 Command and Scripting Interpreter: Windows Command Shell

The PDF file contains embedded JavaScript that utilizes arithmetic obfuscation within the document's metadata to stage an exploit. Critical heuristics indicate the exploitation of multiple Adobe Reader vulnerabilities including CVE-2009-4324 (media.newPlayer), CVE-2009-0927 (Collab.getIcon), CVE-2007-5659 (Collab.collectEmailInfo), and CVE-2008-2992 (util.printf). This process aims to download and execute a second-stage payload.

Heuristics 10

  • 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)
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • Suspicious extracted artifact high 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.
  • String.fromCharCode medium PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0001_000.js
e871183c5d89a3d4f1c75fff3227d96174374174712231ad3dfba955ff9f06cc
pdf-javascript-stream PDF /JS object 1 at offset 0x61F5 368 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
info_arithmetic_stage_000.js
38f5923a7b447b9c28fe65e5b726b6eed0a1c9f3a37405f8f1032ec926cdfb42
deobfuscated-js PDF /Info Producer arithmetic JavaScript at offset 0x23 3642 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).