Malicious PDF — malware analysis report

Static analysis result for SHA-256 b38e3b2adb8dac49…

MALICIOUS

PDF

325.2 KB
MD5: 39ac2166b41aab5f5535dc8afa313c2b SHA-1: 6fa3ac962eae9106ffde1b511deaa0e3d6fd810f SHA-256: b38e3b2adb8dac49f62ccdf94caa69bd3ecafb5375d71dcdbf0d73b06bab3d7d
258 Risk Score

Malware Insights

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

This PDF document contains embedded JavaScript that exploits multiple known vulnerabilities including CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript is obfuscated and appears to be designed to download and execute a second-stage payload, as indicated by the ClamAV detection 'Js.Exploit.Shellcode-18' on an extracted artifact. The deobfuscated JavaScript file 'legacy_pdfkit_stage_000.js' is the primary indicator of malicious activity.

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
c0f4eb578141a551fbf03d355b2b9f29582fd3acc114f6758acaff45491b50fe
pdf-javascript-stream PDF /JS object 8 at offset 0x1E7 3766 bytes
legacy_pdfkit_stage_000.js
b2efac6805cfbc251b0a10c78b9c1c542770240794b5d88ac14f84605db0df00
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x10D1 10946 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s).