Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8e170b125591e23…

MALICIOUS

PDF

132.7 KB
MD5: 6c3f2b45421f27c2ebe873e79cbbf620 SHA-1: 4e3248e1b1246194bf34ea6fa89650d3e36524b8 SHA-256: a8e170b125591e23c8ba4be6d65506180dab8481e49df90dbc90f68cd38bde5a
258 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits multiple known vulnerabilities (CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) related to JavaScript execution within Adobe Reader. The heuristics indicate that this JavaScript is used to launch a second-stage payload, as evidenced by the ClamAV detection 'Js.Exploit.Shellcode-18' on an extracted artifact. The extracted JavaScript files, 'javascript_obj0008_000.js' and 'legacy_pdfkit_stage_000.js', likely contain the malicious code responsible for this behavior.

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
0f93ae02b769ef449bc3f2883bebf4a06293f2fd687d44e9a740d7ed8b36415b
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 2095 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_000.js
652529a1133ed082f13c31f8bfaa42912d27d2982c1182684d2b5f522e58352c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0xA4A 14775 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).