Malicious PDF — malware analysis report

Static analysis result for SHA-256 c838c4a9bec5a57f…

MALICIOUS

PDF

12.2 KB
MD5: 715cac9f1ab0409bd9cfc3e138f8b86e SHA-1: 922e8ad2c993f9b3bb3e6a992b3629f15296bab7 SHA-256: c838c4a9bec5a57fa00ffeb9831c03a0cb834207c5fa9556b0ff9449570a2011
416 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is heavily obfuscated and designed to exploit multiple Adobe Reader vulnerabilities. The heuristics indicate that this JavaScript is decoded by splitting a numeric array and mapping it through a character table, a common technique for delivering exploits. ClamAV detections confirm the malicious nature of the embedded script, identifying it as Js.Exploit.HTML-28.

Heuristics 9

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • 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: Js.Exploit.HTML-28 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-28
  • 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.
  • Suspicious extracted artifact high 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.
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0076_000.js
72390c3d483b5175bd7cc500d91e1d8c72a60777b2f6cdabcd41b52a80bfca4b
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 11557 bytes
Detection
ClamAV: Js.Exploit.HTML-28
Obfuscation or payload: unlikely
split_char_table_stage_000.js
6ffcad89eabbbf9729f8b44b3a3b4fab7cd013d595649adfd742e7276417e697
deobfuscated-js split character-table join decoded JavaScript at offset 0x2D1 3876 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).