Malicious PDF — malware analysis report

Static analysis result for SHA-256 75598dd31a8a8d12…

MALICIOUS

PDF

83.8 KB
MD5: d0e4673a8bca2af99f2af3d9f0918464 SHA-1: d0d42f0d21c8fc2962bea20ff0bee3df90202efe SHA-256: 75598dd31a8a8d12005f8501b19feb4ae2b704eb5c9b2c5fe87300ac53cac7e2
418 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes a character-table-based stager to reconstruct and execute exploit code. Critical heuristics indicate exploitation of multiple Adobe Reader vulnerabilities, including media.newPlayer, Collab.getIcon, Collab.collectEmailInfo, and util.printf. The deobfuscated JavaScript is detected by ClamAV as Js.Exploit.HTML-29, suggesting it's designed to download and execute a secondary payload.

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: Js.Exploit.HTML-29 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-29
  • 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.
  • 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
3c016ef5b9b2be3b8a61732e8576f1a6b95d08079dbc7ed0e052f86a0a87bc69
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 84854 bytes
Detection
ClamAV: Js.Exploit.HTML-29
Obfuscation or payload: unlikely
char_table_stage_000.js
0f42d3b3fbbc92b381dcad709705e7453e280d0b6709a510fd6fc4d4d67fd880
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x2FB 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).