Malicious PDF — malware analysis report

Static analysis result for SHA-256 4854701b7efe18b5…

MALICIOUS

PDF

43.3 KB
MD5: ac144ff798b67710ff55510ec7993101 SHA-1: f53332d7e0b286c25f78c8c7ecb490803b6214c1 SHA-256: 4854701b7efe18b5d731a00778de3b6b95619bc2622d21229aae880d18b48681
78 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1204.002 Malicious File

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT' and 'PDF_JS'. The 'CVE_2009_4324' heuristic specifically points to a known vulnerability related to media player annotations. The deobfuscated JavaScript files, particularly 'legacy_pdfkit_stage_000.js', are likely responsible for exploiting this vulnerability. The script's purpose appears to be downloading and executing a secondary payload, a common technique for initial access.

Heuristics 4

  • 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)
  • 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.
  • 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_obj0008_000.js
0e5062d75afb2b801f8e68029f9853ad52519bc0811457e8b5ee7e5717bf0bd9
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2221 bytes
legacy_pdfkit_stage_000.js
34724b4176b0e989bf73d0fc9ae205c6fc8236b3698a34a94365aab3ab91b629
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xAC8 2756 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
42025b552c7960b53abcd8cd732b01c8d109eccfdfefc352b9826c4d5807d414
deobfuscated-js cross-stage annotation API aliases at offset 0x1E7 81 bytes