Malicious PDF — malware analysis report

Static analysis result for SHA-256 f72a388d2a331e63…

MALICIOUS

PDF

74.7 KB
MD5: d6a7c347d35727ce167aa0471dcb8b4e SHA-1: 8d4b74d7d19fb821eb3d7b33b51e8c6e2cd7a2eb SHA-256: f72a388d2a331e6305d0cf6fe560b8ffc0d51eda6fb2862f5fc017b1810e05d0
166 Risk Score

Malware Insights

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

The PDF file contains obfuscated JavaScript that utilizes a binary-XOR stager. This stager decodes and executes a second-stage payload, exploiting CVE-2007-5659 via the Collab.collectEmailInfo method in Adobe Reader. The script's intent is to download and run further malicious code.

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)
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution
  • 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.
  • 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_obj0004_000.js
02fcd11d68293aa187011d452fd3657a8925b77ae0c01263a648d2e0f8a12a60
pdf-javascript-stream PDF /JS object 4 at offset 0xC0 76181 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s). Carved artifact contains 6 long base64-like blob(s).
binary_xor_stage_000.js
0d891a651370ca5b4f48a97d6ef2de6e0224aa6b9569968b2141a55f9a0b862c
deobfuscated-js binary-XOR decoded JavaScript at offset 0x65AE 1237 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).