Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1c45cabcba4f25c…

MALICIOUS

PDF

12.2 KB Created: 2009-12-16 19:42:91 Authoring application: PDF Library 5.1.10 (via PDF Library 4.8.1)
MD5: d9e63858e983bbfb8a4f0b90965670a4 SHA-1: 25cb675b03efffef3c1a78625fbdceaeea8f0380 SHA-256: b1c45cabcba4f25c34c3ddeb8d4cad51328615b3306b9004ce8c05bffe57873a
278 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 in Adobe Reader, specifically CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. Static analysis recovered a deobfuscated JavaScript stage (legacy_pdfkit_stage_000.js) which was detected by ClamAV as Js.Exploit.Shellcode-18. This indicates the PDF is designed to download and execute a second-stage payload.

Heuristics 8

  • 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.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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_obj0007_000.js
206fd2a27d89f3bda774d899905c00843c346225a80aeb52f6e5baa076af85d3
pdf-javascript-stream PDF /JS object 7 at offset 0x268 37754 bytes
legacy_pdfkit_stage_000.js
1fc474eb915e045cc5d8923b1baf90affe3f32d8240f191440548f40e3c9630f
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x268 9874 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).