Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c1f333a6d1cef1…

MALICIOUS

PDF

60.8 KB
MD5: 3a4b1e5d9759dad5edb8cd71e44dfff4 SHA-1: 81137253b4273b6b073270061533bbefb21ab7e6 SHA-256: b3c1f333a6d1cef1adc5cc2b84cf5657416abae5b05d34b9a1ea2fe00f256105
396 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

The PDF file contains obfuscated JavaScript that utilizes character-table indexing to evade detection. This script exploits several critical vulnerabilities in older versions of Adobe Reader, including CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. The primary function of the script appears to be downloading and executing a secondary payload, as indicated by the 'Win.Trojan.Agent-36331' ClamAV detection.

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: Win.Trojan.Agent-36331 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Agent-36331
  • 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
8de69428e258ba51685a89853651b7c3191025b4efaf5ab8b8de6c3f15e3cb0c
pdf-javascript-stream PDF /JS object 76 at offset 0x2D4 53622 bytes
char_table_stage_000.js
d08e82221436f64b121325ed43a88f575c3c1e496aa3a730c81bdc07086bf5dd
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x324 3858 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).