Malicious PDF — malware analysis report

Static analysis result for SHA-256 8166378befa97d18…

MALICIOUS

PDF

135.6 KB
MD5: eea08d78813a9e89667ffad6c472b9ad SHA-1: 86130b0265aa4f99e010d13c8e416d9627b4376e SHA-256: 8166378befa97d182cc4d282d570b8a9b8a46ed35e39384a115db336d0f3186c
258 Risk Score

Malware Insights

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

The sample is a PDF file that leverages multiple critical vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) by embedding and executing obfuscated JavaScript. The embedded JavaScript is detected as 'Js.Exploit.Shellcode-18' by ClamAV, indicating it likely attempts to download and execute a second-stage payload. The obfuscation and exploitation of known PDF vulnerabilities suggest a downloader or dropper functionality.

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
63879ebe4b058e367233c32e984e19d8b9a1fa63a0404b44188b8cc4c7856b0d
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2105 bytes
legacy_pdfkit_stage_000.js
6517402803d4b2fad14a6daaf686ed7b7fe16a1ecb6c78385fc64301f0318881
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA54 9060 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).