{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-4723", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-03-23T23:22:44.920Z", "datePublished": "2026-03-24T12:30:31.266Z", "dateUpdated": "2026-03-24T20:27:33.416Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"lessThan": "149", "status": "affected", "version": "unspecified", "versionType": "custom"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"lessThan": "149", "status": "affected", "version": "unspecified", "versionType": "custom"}]}], "descriptions": [{"lang": "en", "value": "Use-after-free in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Thunderbird < 149.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Use-after-free in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Thunderbird < 149."}]}], "title": "Use-after-free in the JavaScript Engine component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2013573"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-20/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-23/"}], "credits": [{"lang": "en", "value": "Evyatar Ben Asher, Keane Lucas, Nicholas Carlini, Newton Cheng, Daniel Freeman, Alex Gaynor, and Joel Weinberger using Claude from Anthropic"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-03-24T20:27:33.416Z"}}}}

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