Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9fd3c561a7ef5c9…

MALICIOUS

PDF

133.6 KB
MD5: 734e0a1899046f253dddd68f70bffd49 SHA-1: 507cb07d0f13b0c34cd40a49a8a1ac437b115870 SHA-256: c9fd3c561a7ef5c92bd96b7f7ea7eac515adf61db7b2ee6651fb50ee08fd660a
456 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell T1204.001 Malicious Link T1204.002 Malicious File

This PDF file contains embedded JavaScript that leverages multiple critical vulnerabilities including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The JavaScript is obfuscated using a character table and appears to be a stager designed to download and execute a second-stage payload, as indicated by ClamAV detections on both the PDF and an extracted JavaScript artifact. The primary attack vector is the exploitation of these known PDF reader flaws.

Heuristics 10

  • 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.Agent-36388 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36388
  • 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.
  • Character-table JavaScript eval stager high PDF_JS_CHAR_TABLE_EVAL_STAGER
    PDF JavaScript reconstructs an exploit stage by indexing into a small character table, appending hundreds of one-character fragments, joining the array, and evaluating the result. This static fallback fires only after the bounded decoder recovers an exploit-like stage, so it catches this obfuscation even when no single CVE API signature is available.
  • 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
73eb68f8a917e08e45549836e804e51592069f13105940c1b402d3dde4e9604e
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 120393 bytes
Detection
ClamAV: Js.Exploit.HTML-27
Obfuscation or payload: unlikely
char_table_stage_000.js
1855105a4d25699ea7d148ad4c35a8ca23142fc66b96f5067a45148aaaaeea4f
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x2DC 3888 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).