Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2efe49ae48336f2…

MALICIOUS

PDF

7.3 KB
MD5: cfb9ad0cafaba2486ca26683c4e6722f SHA-1: c7776a5f58701cddfb0ed379c5c5d8d363bda2bc SHA-256: a2efe49ae48336f235decf748d395e21687704d659431a0b6d0b8ba685b2c91f
268 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 multiple critical vulnerabilities including CVE-2009-4324, CVE-2009-0927, and CVE-2007-5659. The embedded JavaScript stream was XOR decoded and further deobfuscated, revealing its malicious nature. ClamAV detected this as Js.Exploit.Shellcode-18, indicating it likely downloads and executes a second-stage payload. The specific attack pattern is a PDF exploit leveraging known CVEs to achieve code execution.

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
6ae96be375ebceae095e073fe3939f564a809256bae0c660262358bddd2d39db
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 27268 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
7b037fa54190e770de0dcf95257be25307cfa7f02f349897a3cc5594440f0b09
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5326 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
db5c1d3958e2b4bba5744133d69607db6a5ba2fb737c60c90a50a046de2b5d8f
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5326 bytes