Malicious PDF — malware analysis report

Static analysis result for SHA-256 b28fe61a7a719a00…

MALICIOUS

PDF

69.7 KB
MD5: 170f9c994f58a03b8917e04018713ac3 SHA-1: 5d7e1007cd3aa4e4d455c0b949474b815686ee84 SHA-256: b28fe61a7a719a00726a00a88816ad299e8071e35c629f01893a5adc6b8eab51
258 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

This PDF document is malicious, leveraging multiple critical vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through embedded JavaScript. The heuristics indicate that the PDF launcher concatenates info fields, extracts characters, and evaluates the result. An extracted artifact, 'legacy_pdfkit_stage_000.js', was flagged by ClamAV as 'Js.Exploit.Shellcode-18', suggesting it's a JavaScript-based exploit. The script's obfuscated nature and the exploit signatures point towards a downloader or initial execution stage for further malicious activity.

Heuristics 7

  • 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)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (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.
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0008_000.js
85f1e9018e079170070159f6db5e04e1435491b8f1d434c461fc66ba776f06bd
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2105 bytes
legacy_pdfkit_stage_000.js
045518b5d2528577a99478a4ee42221cb398fddde352f769a61e51f91dc8c1d3
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA54 4560 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).