{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-6746", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-04-21T12:40:43.779Z", "datePublished": "2026-04-21T12:40:44.148Z", "dateUpdated": "2026-04-22T15:08:34.207Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "115.35", "lessThanOrEqual": "115.*", "versionType": "rpm"}, {"status": "unaffected", "version": "140.10", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "150", "lessThanOrEqual": "*", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.10", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "150", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10."}]}], "title": "Use-after-free in the DOM: Core & HTML component", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2014596"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-30/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-31/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-32/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-33/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-34/"}], "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": "2026-04-21T23:34:37.002Z"}}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-416", "lang": "en", "description": "CWE-416 Use After Free"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-04-22T15:08:29.668813Z", "id": "CVE-2026-6746", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-22T15:08:34.207Z"}}]}}

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{"bugzilla": {"description": "firefox: Use-after-free in the DOM: Core & HTML component", "id": "2460112", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460112"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nUse-after-free in the DOM: Core & HTML component"], "name": "CVE-2026-6746", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "rhel10/firefox-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-21T12:40:44Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-6746\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-6746\nhttps://www.mozilla.org/security/advisories/mfsa2026-30/#CVE-2026-6746\nhttps://www.mozilla.org/security/advisories/mfsa2026-31/#CVE-2026-6746\nhttps://www.mozilla.org/security/advisories/mfsa2026-32/#CVE-2026-6746"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[115.35,115.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.10,140.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[150,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}], "analysis": {"en": {"generated_at": "2026-04-28T16:18:44.688457+00:00", "value": {"mitigation_remediation": ["Upgrade to a Mozilla Firefox or Thunderbird release that includes the fix (Firefox\u00a0150 or newer, Firefox ESR\u00a0115.35 or\u00a0140.10, Thunderbird\u00a0150 or newer, Thunderbird ESR\u00a0140.10).", "Enable automatic updates or run the update utility regularly to ensure that the latest security fixes are applied without manual intervention.", "If an upgrade cannot be performed immediately, mitigate the risk by disabling JavaScript execution or applying content\u2011safety restrictions for untrusted web pages and mail content until the official patch is deployed."], "summary": {"action": "Patch Now", "impact": "Use\u2011after\u2011free potentially enabling arbitrary code execution"}, "threat_synthesis": {"affected_systems": "Any installation of Mozilla Firefox or Thunderbird older than Firefox\u00a0150, Firefox ESR\u00a0115.35, Firefox ESR\u00a0140.10, Thunderbird\u00a0150, or Thunderbird\u00a0140.10 is vulnerable. The issue affects both standard and ESR builds, so users on any of the listed versions are at risk.", "description_and_impact": "This vulnerability is a use\u2011after\u2011free condition located in the DOM core and HTML component of the Mozilla codebase. The flaw permits access to a memory object after it has been freed, which corresponds to CWE\u2011416 and CWE\u2011825. The potential impact is that an attacker could trigger the bug to execute arbitrary code in the context of the browser or mail client, compromising confidentiality, integrity, or availability of the affected system.", "risk_and_exploitability": "The CVSS score of 7.5 indicates high severity for a use\u2011after\u2011free bug in a mainstream browser. The EPSS score is less than 1%, so the likelihood of exploitation is very low, and the vulnerability is not included in the CISA KEV catalog. Based on the description, it is inferred that the likely attack vector is the delivery of malicious content through a web page or embedded HTML that triggers the DOM bug during normal browsing or mail processing."}}}}, "created": "2026-04-21T17:00:11.952872+00:00", "updated": "2026-04-28T16:30:35.088708+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}