Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4a16a6507ce3e9a…

MALICIOUS

PDF

7.0 KB
MD5: 77137b0c8125eae9b5303776a8dd750f SHA-1: 64ab1e94a8b41c0341fec45f203539b4c5da68fd SHA-256: c4a16a6507ce3e9aa65f8977f4d2e2a8c5014f0e849bd91eb3c6b91baafe3f07
266 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1071.001 Web Protocols

The PDF file contains embedded JavaScript that leverages multiple critical vulnerabilities including CVE_2009_4324, CVE_2009_0927, and CVE_2007_5659. The JavaScript is XOR decoded and obfuscated, and analysis indicates it likely attempts to download and execute a second-stage payload, as evidenced by ClamAV detection of 'Js.Exploit.Shellcode-18' in an extracted artifact. The presence of multiple exploit-related heuristics strongly suggests a malicious intent to compromise the user's system.

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)
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • 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_obj0039_000.js
ae88227483545a533e873e6f4e7e5aef7d38d6cdead89d9fdc971c68fb0c6c35
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 22983 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
5b9713b24ca2f3ad63839b771c3e3c53bdc066d7fc4958eaf906da5deae096f6
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5344 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
1498a25280444fc9e04889a0622422b714ff4dc559d344fcc836b48a36a0ed2e
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5344 bytes