Malicious PDF — malware analysis report

Static analysis result for SHA-256 b70b890d3e6a4226…

MALICIOUS

PDF

12.0 KB Created: 2009-11-23 19:44:70 Authoring application: PDF Library 3.4.5 (via PDF Library 2.8.7)
MD5: 5c4aab69c3c4bb35c08550dc45bdba61 SHA-1: 6e4e582d73b4b0b43193143372d3aeddff510d4c SHA-256: b70b890d3e6a4226109308bfc9e31989691aae7af3af6583a302b32d884910fb
278 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

This PDF document exploits multiple critical vulnerabilities including CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992 by leveraging embedded JavaScript. The embedded JavaScript, identified as legacy_pdfkit_stage_000.js, is heavily obfuscated and detected by ClamAV as Js.Exploit.Shellcode-18. The primary function of the script appears to be downloading and executing a second-stage payload, indicated by the exploit kit indicators and extracted artifact.

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
dc35b337b4f39ee9e9088caf4703749c4f9b44be045c4bd4b32f7bfa7bbe0e6d
pdf-javascript-stream PDF /JS object 7 at offset 0x268 37589 bytes
legacy_pdfkit_stage_000.js
f1f08a261bc346cf8327d1436afb83ce420c70b550a97cf7cde924b2738fcf29
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x268 9868 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).