Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb82ee8cf1087693…

MALICIOUS

PDF

13.6 KB
MD5: 291689cfd29e29442b1c2513a0bf3149 SHA-1: 77c3465f2db55d1dcadcdfa689aef21f192b7714 SHA-256: cb82ee8cf1087693b528d6c6f6100503cd51fd452e8abd7f89fde17fc3ed79c6
298 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059.001 PowerShell T1059.007 JavaScript

The PDF file contains embedded JavaScript that utilizes custom Base64 decoding to unpack and execute exploit code targeting Adobe Reader vulnerabilities CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The extracted artifact 'custom_b64_stage_000.js' was detected by ClamAV as 'Js.Exploit.Shellcode-18', indicating it likely contains shellcode to further compromise the system. The script's primary intent is to download and execute a second-stage payload.

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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits
  • 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
7557b399933968ede747898dff95d0342f5dc5a50d8660babe2d34a40f5c839e
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 13205 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
custom_b64_stage_000.js
10c1d50a1874f923a8ad182de58b0d07f0e08636418a032dc6b0a078de507193
deobfuscated-js custom Base64 decoded JavaScript layer 2 (PDF /JS object 8) at offset 0x6E8 6500 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s).