Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8fae1d54c6aca99…

MALICIOUS

PDF

132.6 KB
MD5: 598789b5c9e711519c3f084d03bf3da5 SHA-1: 5fff38808911432a57fd9f3319ed768ca9ba0ee9 SHA-256: f8fae1d54c6aca99528716c3328a85250fbfdb6af413c4a23d34dcfcbbdc9a9e
456 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.001 Malicious Link: Malicious JavaScript T1204.002 Malicious Link: Malicious File

The PDF file contains heavily obfuscated JavaScript that utilizes character-table indexing to reconstruct and execute exploit code. Critical heuristics indicate exploitation of multiple CVEs related to PDF JavaScript execution, including media.newPlayer, Collab.getIcon, Collab.collectEmailInfo, and util.printf. The deobfuscated JavaScript, named 'char_table_stage_000.js', is likely responsible for downloading and executing a second-stage 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: 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
a49a79b7a95aa9d72217875e8fbc49a003c327ba8ef4a6ad2c148eada17bddab
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 119406 bytes
Detection
ClamAV: Js.Exploit.HTML-27
Obfuscation or payload: unlikely
char_table_stage_000.js
8ff5d7fbb259e75322c78a0a845db2b9eb3e9b1b646af3a4a934dab06fe4dea4
deobfuscated-js char-table indexed JavaScript (PDF /JS object 76) at offset 0x2DC 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).