Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b369be77b5eb3e9…

MALICIOUS

PDF

6.7 KB
MD5: 463f4a07c8945b05f270c11d2e5504ba SHA-1: 5ce1d5f565b8704fb20426c9d8e4bd124bea77c6 SHA-256: 8b369be77b5eb3e9f454471d883091f7d1a79e8bb26695238b51116e82d33add
266 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages multiple critical vulnerabilities including CVE-2009-4324, CVE-2009-0927, and CVE-2007-5659. The JavaScript is XOR decoded and then evaluated, indicating an attempt to execute arbitrary code. ClamAV detected this as Js.Exploit.Shellcode-18, further confirming its malicious nature. The primary intent appears to be the execution of a second-stage payload, likely downloaded from a remote source, though no specific URLs were extracted.

Heuristics 8

  • 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)
  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0039_000.js
0c0e222fa6b48d9813515f0889b5fb8011cfd6b5d67a7937cbc706826b10b029
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 20671 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
e71bce33d303a704db1ae7ac3ddcdedcf008ba987e73a469e26089921d570909
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5380 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
727b0fc42b667c4cb740f65b825b0efdab30bc0d51f47e0485476a97e370454c
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5380 bytes