CVE-2026-6776
Full vulnerability record from the local CVENow database.
Description
Incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-04-21 13:16:23.350000
Last modified
2026-10-26 00:10:00.150000
View original CVE JSON
{
"id": "CVE-2026-6776",
"sourceIdentifier": "[email protected]",
"published": "2026-04-21T13:16:23.350",
"lastModified": "2026-10-26T00:10:00.150",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10."
},
{
"lang": "es",
"value": "Condiciones de contorno incorrectas en el componente de red WebRTC. Esta vulnerabilidad se corrigió en Firefox 150, Firefox ESR 140.10, Thunderbird 150 y Thunderbird 140.10."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"version": "140.10",
"lessThanOrEqual": "140.*",
"versionType": "rpm",
"status": "unaffected"
},
{
"version": "150",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
{
"version": "140.10",
"lessThanOrEqual": "140.*",
"versionType": "rpm",
"status": "unaffected"
},
{
"version": "150",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
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"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
}
],
"ssvcV203": [
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"timestamp": "2026-04-21T13:49:53.035013Z",
"id": "CVE-2026-6776",
"options": [
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"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
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"role": "CISA Coordinator",
"version": "2.0.3"
}
}
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},
"weaknesses": [
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"description": [
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"lang": "en",
"value": "CWE-119"
}
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}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
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"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*",
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"matchCriteriaId": "15AF037C-5C86-48EB-B1DE-3AC100A34596"
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"references": [
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2021770",
"source": "[email protected]",
"tags": [
"Permissions Required"
]
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-30/",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-32/",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-33/",
"source": "[email protected]",
"tags": [
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{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-34/",
"source": "[email protected]",
"tags": [
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}