Malicious PDF — malware analysis report

Static analysis result for SHA-256 38dc13cb96c36b3e…

MALICIOUS

PDF

13.4 KB
MD5: ce5c52bcd57ca7782a6573f8d012b05d SHA-1: 857a96606de727adb4c9ba5d30085f7610e988df SHA-256: 38dc13cb96c36b3e5d50c30033f5522bbb512d355db1c4047573719fc5b221f7
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1059.007 JavaScript

The critical heuristic CVE_2007_5659 indicates the sample exploits a known vulnerability in Adobe Reader. The PDF_BINARY_XOR_JS_STAGER heuristic confirms that obfuscated JavaScript is used as a stager. This JavaScript is likely responsible for downloading and executing a secondary payload, although the specific download URL or payload is not directly recoverable from the provided evidence.

Heuristics 7

  • 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: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • Binary-XOR JavaScript stager high PDF_BINARY_XOR_JS_STAGER
    PDF JavaScript stores viewer-version payload branches as long binary digit strings, XORs each bit pair, converts 8-bit chunks with String.fromCharCode, and evals the recovered exploit stage.
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0049_000.js
69d588dfef1b3bee9d9677806bceccb273781bf90964a6c0999f55f0d7f4238e
pdf-javascript-stream PDF /JS object 49 at offset 0xA 79816 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 6 long base64-like blob(s).
binary_xor_stage_000.js
0763c6e73048e30deca834065d9b02da398cd9f62e481cf18a617ddd9f6b1f14
deobfuscated-js binary-XOR decoded JavaScript at offset 0x464 1336 bytes