Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0d97d633c553de4…

MALICIOUS

PDF

76.2 KB
MD5: 0a86aea47d541eb81e71712ad3ca4d87 SHA-1: 28029ad58df4dffea1cd79d9adcef7dfecb4081a SHA-256: c0d97d633c553de46683ea75854f7f9b695254dfe06fdbbc4c5ffa39d8080995
166 Risk Score

Malware Insights

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

The PDF file contains obfuscated JavaScript that utilizes a binary-XOR stager to deobfuscate and execute a second-stage payload. The critical heuristic firing indicates exploitation of CVE-2007-5659 via the Collab.collectEmailInfo method, which is used to launch the exploit. The recovered JavaScript is XOR-encoded and then evaluated, suggesting it's designed to download and execute further malicious content.

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
848abb7b95d8c43ee434345d401bbd9820c4719be4d6659b10c1c0135325a0ea
pdf-javascript-stream PDF /JS object 4 at offset 0xC0 77722 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
a2caa10c1e137c3c7680c570775fc47e866b752224a4ee73b3fcd3357aaa8c9e
deobfuscated-js binary-XOR decoded JavaScript at offset 0x3D7 1273 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).