CVE-2026-7966

Description

Insufficient validation of untrusted input in SiteIsolation in Google Chrome prior to 148.0.7778.96 allowed a remote attacker who had compromised the renderer process to bypass site isolation via a crafted HTML page. (Chromium security severity: Medium)

CVSS Details

CVSS Score

3.1

Severity

LOW

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Configurations (Affected Products)

cpe:2.3:a:google:chrome:*:*:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:* - NOT VULNERABLE

Google Chrome < 148.0.7778.96

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

<!--
Conceptual Proof of Concept for CVE-2026-7966
Description: Demonstrates the attempt to bypass site isolation.
Note: This requires a renderer compromise to be effective.
-->
<html>
<body>
<h1>CVE-2026-7966 PoC</h1>
<script>
    // Step 1: Assume the attacker has compromised the renderer process.
    // Step 2: Craft a specific input to trigger insufficient validation.
    
    function attemptBypass() {
        // In a real scenario, this would exploit the specific validation flaw
        // in SiteIsolation to access cross-origin data.
        
        const targetUrl = "https://target-site.com/secret";
        
        // Attempt to open or reference the target window
        // The exploit logic would manipulate the DOM or navigation events
        // to confuse the browser's SiteIsolation logic.
        
        console.log("Attempting to bypass Site Isolation for: " + targetUrl);
        
        // Hypothetical exploit payload would go here
        // e.g., exploiting a specific race condition or input validation bug.
    }

    // Trigger on user interaction as per UI:R requirement
    document.body.onclick = attemptBypass;
    console.log("Click page to trigger exploit");
</script>
<p>Click this page to test the vulnerability.</p>
</body>
</html>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-7966
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-7966
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-7966/
[4] VulDB https://vuldb.com/cve/CVE-2026-7966
[5] https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop.html
[6] https://issues.chromium.org/issues/497341787

Raw JSON Data

JSON

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