Malicious PDF — malware analysis report

Static analysis result for SHA-256 42659b5a0ce169d2…

MALICIOUS

PDF

25.8 KB Created: 2011-72-51 03:25:00
MD5: 408a1a20d44542405f65730dd16e52b0 SHA-1: 758cf418f85aa95cfcbcd2993c35d6f0b1012f61 SHA-256: 42659b5a0ce169d252ba7858956eec66400ee77f9a495fcf19b928dabd862b7f
356 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages arithmetic operations within the document's metadata to deobfuscate and execute an exploit stage. This stage targets multiple Adobe Reader vulnerabilities, including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992, indicating a clear intent to compromise the user's system through a known exploit chain. The recovered JavaScript is heavily obfuscated, but the presence of these specific CVEs strongly suggests the execution of a second-stage payload.

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.
  • 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
3406832a15567ff08562de67306623355820d36c9564ab01b9f09a2064fa09c3
pdf-javascript-stream PDF /JS object 1 at offset 0x646E 467 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
0cd8652e9c1c7063ddbe0cf15013925848ab49f3020f95ab717323453d724a6f
deobfuscated-js PDF /Info Producer arithmetic JavaScript at offset 0x23 3734 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).