Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7242032fd60bd3e…

MALICIOUS

PDF

7.9 KB
MD5: eace7219dc7379b2da813f65118b9059 SHA-1: 76f9894c3f384d227c93c4ef2d7f25e5bb67d356 SHA-256: b7242032fd60bd3ebede3b4d1844d9befc1be9f7141106a9e6b2b731f36b6af3
346 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell T1059.003 Windows Command Shell

The PDF document contains embedded JavaScript that is heavily obfuscated and decodes multiple layers. The heuristics indicate exploitation of Adobe Reader vulnerabilities CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The primary intent appears to be executing a second-stage payload via JavaScript eval() calls, as evidenced by the 'Js.Exploit.Shellcode-18' ClamAV detection on an extracted artifact. No specific family could be identified.

Heuristics 10

  • 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.
  • OpenAction trigger high PDF_OPENACTION
    PDF has an /OpenAction — code runs automatically when opened
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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_obj0009_000.js
c4663a761b4fabfed2afabd5fe7fed2bb523dd1ab87142b7724c5af881b7f826
pdf-javascript-stream PDF /JS object 9 at offset 0xD6 19744 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
custom_b64_stage_000.js
64a17fb775f5c379657e48d8c77e88161428b488ee10e84bfae0636e930325a0
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 9) at offset 0x436 10599 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).