CVE-2026-6758
Full vulnerability record from the local CVENow database.
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-04-21 13:16:21.770000
Last modified
2026-10-26 22:10:00.163000
View original CVE JSON
{
"id": "CVE-2026-6758",
"sourceIdentifier": "[email protected]",
"published": "2026-04-21T13:16:21.770",
"lastModified": "2026-10-26T22:10:00.163",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150 and Thunderbird 150."
},
{
"lang": "es",
"value": "Uso después de liberación en el componente javascript_disabled: WebAssembly. Esta vulnerabilidad se corrigió en Firefox 150 y Thunderbird 150."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"version": "150",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
{
"version": "150",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
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"cvssData": {
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"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
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-04-22T15:06:30.502426Z",
"id": "CVE-2026-6758",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
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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-416"
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"configurations": [
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"references": [
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2013619",
"source": "[email protected]",
"tags": [
"Permissions Required"
]
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-30/",
"source": "[email protected]",
"tags": [
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{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-33/",
"source": "[email protected]",
"tags": [
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}