Malicious PDF — malware analysis report

Static analysis result for SHA-256 9979213228336e20…

MALICIOUS

PDF

12.5 KB
MD5: 4e91a03ae6e7600e66ee0f930a2f87b2 SHA-1: a951e9801d4916fe47a2e14c2eeee02770aa3dc1 SHA-256: 9979213228336e205aae6f5ea42b0c453be86ed2c626a474b04713cc9efaacd3
416 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that is heavily obfuscated and designed to exploit multiple Adobe Reader vulnerabilities. The heuristics indicate that this JavaScript is decoded by splitting a long numeric array, mapping indices through a character table, and then evaluating the result. This technique is commonly used to deliver a second-stage payload, as suggested by the ClamAV detection of Js.Exploit.HTML-28 on both the original PDF and an extracted JavaScript artifact.

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: Js.Exploit.HTML-28 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Js.Exploit.HTML-28
  • 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.
  • 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
5e64d443e1873cef5f079a7d1c4a3db9b6dfcde0f8a4dba1c39c98f16ee4a96e
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 11865 bytes
Detection
ClamAV: Js.Exploit.HTML-28
Obfuscation or payload: unlikely
split_char_table_stage_000.js
5fe5c9988866bb6f4eabb46bb88c630125b9b6c23ef7d38bb5157bf64a619c55
deobfuscated-js split character-table join decoded JavaScript at offset 0x2D1 3936 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).