Malicious PDF — malware analysis report

Static analysis result for SHA-256 b447ca098a2e94d1…

MALICIOUS

PDF

299.0 KB
MD5: eb870bdc59ee55af5cb7131a3f963d20 SHA-1: 825f2eeb127dae302e550a68e9ac774dcc5acd72 SHA-256: b447ca098a2e94d14f2e26dc20b4a5454cd2c91b98226e65d2161260683ec373
318 Risk Score

Malware Insights

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

The PDF exploits multiple CVEs related to JavaScript execution within PDF documents. The embedded JavaScript, specifically 'legacy_pdfkit_stage_000.js', is heavily obfuscated but detected by ClamAV as a malicious exploit. This script is likely responsible for downloading and executing 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: Pdf.Exploit.Agent-36307 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36307
  • 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
323858738e259adc7cea670500dff803a9cb1d86fbf380f9cb189263f5672386
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 3462 bytes
Detection
ClamAV: Pdf.Exploit.Agent-36307
Obfuscation or payload: unlikely
legacy_pdfkit_stage_000.js
c151d738b42ada17a26552dadc5f5a5c09d1d1d495c413fc1cc890d4b5afb006
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xFA1 20129 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s).