Malicious PDF — malware analysis report

Static analysis result for SHA-256 253dee7d9fd23d19…

MALICIOUS

PDF

6.7 KB
MD5: 9536f240cb07ec47f4e5cf9c3043460b SHA-1: e9da4251c1c84c970c081d182764eb4328ee4174 SHA-256: 253dee7d9fd23d197d3e29f99a6d60fcdb0a55abc62d847a5347c800eb7168d0
266 Risk Score

Malware Insights

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

The PDF document contains embedded JavaScript that exploits multiple CVEs (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659) to achieve code execution. The embedded JavaScript is XOR-decoded and further deobfuscated, indicating an attempt to hide malicious activity. The deobfuscated scripts are likely responsible for downloading and executing a second-stage payload, as suggested by the ClamAV detection of 'Js.Exploit.Shellcode-18'. The extracted filenames also point to a staged JavaScript execution.

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
5ce031b63fac2c75b4c20e50c93fe8829964265bbcee46b48639a469f154102d
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 21275 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
22c32b66bae6a090197bd744fcd5c9393fcc68e273e0d9d97ba7f0da2e9ecf75
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5398 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
3ef5f7fe46122bf998f07f49cfa377de87f8bd3c04987b36fbb097af14642fa2
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5398 bytes