Malicious PDF — malware analysis report

Static analysis result for SHA-256 5023a4e393e2f6fd…

MALICIOUS

PDF

118.5 KB
MD5: fc612d66343e01958c94411e076c3eb4 SHA-1: 78d0554ba94edf58ab6db4ec410bb5481887d8b2 SHA-256: 5023a4e393e2f6fdc3e00761849724101f759d24de9ebe8a2500e09acb631d20
496 Risk Score

Malware Insights

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

This PDF file contains multiple embedded JavaScript streams that are heavily obfuscated and utilize substitution-hex decoding. The heuristics indicate that these scripts are designed to exploit several Adobe Reader vulnerabilities, including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The primary function of the script appears to be downloading and executing a second-stage payload, leveraging the identified CVEs to achieve code execution within the user's Adobe Reader application.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 12

  • 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)
  • Multi-CVE Adobe Reader JavaScript exploit kit critical PDF_ADOBE_READER_MULTI_CVE_JS_KIT
    One recovered JavaScript stage contains multiple version-gated Adobe Reader exploit branches. This is stronger evidence than independent API keywords: the PDF is selecting old Reader vulnerabilities by viewer version and running heap-sprayed Acrobat JavaScript exploit paths.
  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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. (matched inside decoded stream)
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
ed813e3bd5436f3912d158d452534996f0a3d4a3c4b15b26ec8a0e27acb3ea1c
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626961 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).
legacy_pdfkit_stage_000.js
09960ffeb497c666fe441d0be652f78aba0c95f94d8f1b777070b3bab84b2326
deobfuscated-js double percent-decoded annotation JavaScript at offset 0x143 262116 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 603 long base64-like blob(s).
legacy_pdfkit_stage_001.js
647a01a652f68a4157c0d9a6cd387226b1a926108e7689f7e9695d73174c8a95
deobfuscated-js comment-padded substitution-hex decoded JavaScript at offset 0x143 10413 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 12 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).