Malicious PDF / .PHP — malware analysis report

Static analysis result for SHA-256 b0e78d53c9fd4ef8…

MALICIOUS

PDF / .PHP

76.2 KB
MD5: 7bee5974f3e9ddb431349d18c8ffe239 SHA-1: 21aa482ddc2e7363b97290078489a2cf88d9b56c SHA-256: b0e78d53c9fd4ef8cf945ed0d3c055d5929ce2b4393b83979e7c5d68b153f52e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1027 Obfuscated Files or Information

The PDF file contains obfuscated JavaScript that utilizes a binary XOR stager. This stager decodes and executes further JavaScript, which is designed to exploit the CVE-2007-5659 vulnerability in Adobe Reader. The script's primary function appears to be downloading and executing a second-stage payload, indicated by the use of eval() and String.fromCharCode, and the critical CVE_2007_5659 heuristic firing.

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
2317e64f83362f47fbcdf0d4632cad4a2eb407015b556aa8b77c39b9c5020e75
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
9f2e93d9307bbfd4bba986d31eaac349e5fa7226a29722c25c7db7004b08045c
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).