Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3e3fc2d3097abe8…

MALICIOUS

PDF

52.4 KB Authoring application: sli
MD5: 8b81e448c9386fc1f42f64d26630b9e9 SHA-1: 10b042e2c8b8872f3c603e6858a228709fce9b20 SHA-256: a3e3fc2d3097abe81db169c92a600053e265754554003416738b9bfe9736957c
378 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1059.001 Command and Scripting Interpreter: JavaScript T1190 Exploit Public-Facing Application

This PDF file contains embedded JavaScript that exploits multiple known Adobe Reader vulnerabilities including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript is obfuscated using an array character-table decoding method. The primary purpose appears to be the execution of a second-stage payload, as indicated by the ClamAV detection of 'Pdf.Exploit.Dropped-91' and the extracted JavaScript artifact '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: Pdf.Exploit.Dropped-91 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-91
  • 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_obj0076_000.js
e8f2c68873c0cbc7ab0650ebe0bb79edc328b10014c75bc3795638b564c6bcd4
pdf-javascript-stream PDF /JS object 76 at offset 0x41A 52315 bytes
Detection
ClamAV: Js.Exploit.HTML-28
Obfuscation or payload: unlikely
array_char_table_stage_000.js
832acb24f51bde4641a24a5e4ed9f971e01fd2c87da99b8361eb4afb9e5c80e9
deobfuscated-js array character-table decoded JavaScript at offset 0x42B 3848 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).