Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9e3a8cc82dfb23f…

MALICIOUS

PDF

12.1 KB
MD5: 1a0251d6bf6464b8308fb40f6a58b7f2 SHA-1: e3b937e54c4f7b2af6bb144346c03316118beb04 SHA-256: a9e3a8cc82dfb23ff84f5795ed2f7a2cd52cd0243e36bc811d04fce617d75edc
378 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 joining split character tables, a common technique for delivering exploits. The ClamAV detection 'Js.Exploit.HTML-28' further confirms the malicious nature of the embedded script, which likely downloads and executes a second-stage payload.

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.
  • 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
c7124ccc5ea4cd898c5c6a975c535113fdc9f055ace23d2ce97919a1c0a7ba04
pdf-javascript-stream PDF /JS object 76 at offset 0x2C2 11499 bytes
Detection
ClamAV: Js.Exploit.HTML-28
Obfuscation or payload: unlikely
split_char_table_stage_000.js
01974ca313c2d7ff54607aab417553fc3044af1c76eab0e94ec9b4ee4d8d3208
deobfuscated-js split character-table join decoded JavaScript at offset 0x2D1 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).