Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5fba4c053894623…

MALICIOUS

PDF

7.5 KB
MD5: 63ce9ee3c29875dc6b3f609f24563d85 SHA-1: bf5d013a673c2db30469377e1112f4c55f20ed9f SHA-256: f5fba4c053894623341db00713f27b0f09d1bf4f26bcff1373f2ce7622e7b0e4
268 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.001 PowerShell T1059.003 Windows Command Shell T1059.007 JavaScript

The PDF file contains embedded JavaScript that exploits multiple known vulnerabilities including CVE-2009-4324, CVE-2009-0927, and CVE-2007-5659. The embedded JavaScript was further identified by ClamAV as Js.Exploit.Shellcode-18. The script's intent is to download and execute a second-stage payload, indicated by the shellcode detection.

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)
  • 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)
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSEOF. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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
4d9441b7d2d5ca7e50751e8da0841dc2018a251f246c61db00126cbef0dfa53c
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 28887 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
0cc5a53f682a359bec809c02d2d557906d5fc830e8900d5a7ce7fec4ab3ab5aa
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5488 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
e8980e72966bc2cfd2428a2d5dfa3d696d105651f5d9dd05307033abde585623
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5488 bytes