Malicious PDF — malware analysis report

Static analysis result for SHA-256 93d3a00299c5675d…

MALICIOUS

PDF

76.2 KB Created: 2009-12-05 19:43:24 Authoring application: PDF Library 4.4.6 (via PDF Library 9.9.4)
MD5: f38ccacc968377cf39d3903670c93217 SHA-1: 8926cce4f9c2fd3b050dd82419026f42c2c61300 SHA-256: 93d3a00299c5675dece68800dc2167582a71586c7e7db81e9a738ec69c6e1ae4
338 Risk Score

Malware Insights

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

The PDF exploits multiple Adobe Reader vulnerabilities, specifically targeting Collab.getIcon, Collab.collectEmailInfo, and util.printf functions. Static analysis recovered obfuscated JavaScript, which was deobfuscated into 'legacy_pdfkit_stage_000.js'. This script likely downloads and executes a second-stage payload, as indicated by ClamAV detections on extracted artifacts. The exploitation of known CVEs points to a classic exploit kit delivery mechanism.

Heuristics 9

  • 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: Pdf.Exploit.Agent-36110 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36110
  • 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
078e380e8972e3459f7dff3b455876be1a10fb144260f8d0d0ea5e85f01214b8
pdf-javascript-stream PDF /JS object 7 at offset 0x1A5 38513 bytes
legacy_pdfkit_stage_000.js
d675062e2ea7d3280e2fc62bb6113730ca0b30683dbebb8eb0538548b6358f6d
deobfuscated-js numeric array subtract-key decoded JavaScript at offset 0x1A5 10102 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).