Malicious PDF — malware analysis report

Static analysis result for SHA-256 be26fa9d93778a01…

MALICIOUS

PDF

61.3 KB
MD5: 81d048da0111df4434c34623fea2bc7d SHA-1: 92f0b574f7b528036f8d38ed9f1ee79fedd3a978 SHA-256: be26fa9d93778a0120545e52aa4435f1c214a88f034f21bc6b0b4a3a4c9ddfbb
358 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell Script: JavaScript Execution T1204.001 Malicious Link: Malicious Link T1566.001 Phishing: Spearphishing Attachment T1204.002 Malicious Link: Exploitation for Client Execution

The PDF file contains embedded JavaScript that utilizes character-table indexing for obfuscation, a technique commonly used to evade detection. Critical heuristics indicate exploitation of multiple CVEs (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) related to JavaScript execution within PDF documents. The deobfuscated JavaScript likely serves as a stager to download and execute a secondary payload, as suggested by the 'eval_char_append_stage_000.js' filename and the nature of the heuristics.

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.Agent-36333 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36333
  • 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.
  • 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
a9984f4f9136fcbf8741ef7fd88c545578249a1b868f9956fa1a350e03f59ce1
pdf-javascript-stream PDF /JS object 76 at offset 0x2D4 54127 bytes
eval_char_append_stage_000.js
3b8284d4b23982d4d674eb47407fb8165d06ea23902fc55789baa19393351fe3
deobfuscated-js eval character-table append decoded JavaScript at offset 0x300 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).