Malicious PDF — malware analysis report

Static analysis result for SHA-256 b040656fb2437ae5…

MALICIOUS

PDF

69.6 KB
MD5: c3e21196cbbafd80e53d79ae8c3960c3 SHA-1: a922815254b32e884d5bb353134aafdc3341a5f1 SHA-256: b040656fb2437ae5d56f037eed06e80c730cb69d164578fce67b5647b56ace1a
258 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple known vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) through the use of `Collab.getIcon`, `Collab.collectEmailInfo`, and `util.printf` functions. The extracted artifact `legacy_pdfkit_stage_000.js` was flagged by ClamAV as `Js.Exploit.Shellcode-18`, indicating it likely contains shellcode. The JavaScript's obfuscated nature and the exploitation of these specific CVEs suggest it's designed to download and execute a secondary malicious payload.

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
bd55ce3975f335ef89a68e6bc3aaed972e9b7d9d7fd08d10f9734dea9975fa0d
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2089 bytes
legacy_pdfkit_stage_000.js
045518b5d2528577a99478a4ee42221cb398fddde352f769a61e51f91dc8c1d3
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA44 4560 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).