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{"bugzilla": {"description": "firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component", "id": "2450719", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450719"}, "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-733", "details": ["A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:\nJIT miscompilation in the JavaScript Engine: JIT component"], "name": "CVE-2026-4698", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "rhel10/firefox-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "rhel10/thunderbird-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-03-24T12:30:27Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-4698\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-4698\nhttps://www.mozilla.org/security/advisories/mfsa2026-22/#CVE-2026-4698\nhttps://www.mozilla.org/security/advisories/mfsa2026-24/#CVE-2026-4698"], "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": "affected", "versions": {"scheme": "generic", "value": "[0,149)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,115.34)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox ESR", "source": "cna", "vendor": "Mozilla"}, "product": "firefox_esr", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,140.9)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox ESR", "source": "cna", "vendor": "Mozilla"}, "product": "firefox_esr", "vendor": "mozilla"}], "analysis": {"en": {"generated_at": "2026-04-13T16:20:07.488193+00:00", "value": {"mitigation_remediation": ["Upgrade Mozilla Firefox to version 149 or later, or to ESR 115.34 or 140.9 if using an extended\u2011support release.", "Upgrade Mozilla Thunderbird to version 149 or later, or to ESR 140.9 if using an extended\u2011support release.", "If an update cannot be applied immediately, avoid using affected browsers and consider disabling JavaScript or restricting access to untrusted web content."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "The issue is present in Mozilla Firefox releases prior to version 149 and in Firefox Extended Support Release (ESR) versions older than 115.34 and 140.9. Mozilla Thunderbird is affected in releases older than 149 and ESR releases older than 140.9. Users running any of these versions are vulnerable until they upgrade to a fixed release.", "description_and_impact": "A Just\u2011In\u2011Time compiler miscompilation flaw in the JavaScript engine allows an attacker to influence how compiled code is executed, potentially enabling arbitrary code execution within the browser context. The vulnerability is rated with a CVSS score of 9.8, indicating a critical level of risk. No public exploit has yet been observed, but the severity suggests that successful exploitation could compromise confidentiality, integrity, and availability of the user\u2019s system.", "risk_and_exploitability": "Given the high CVSS score, the flaw poses a significant risk. The EPSS score is under 1%, indicating a low probability of real\u2011world exploitation at present, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. The likely attack vector is via malicious web content that triggers JavaScript execution in the browser context, allowing the JIT to generate unsafe code (inferred). Detailed exploitation steps are not disclosed, so the exact conditions required remain unknown."}}}}, "created": "2026-03-25T11:48:10.837578+00:00", "updated": "2026-04-14T16:43:31.298386+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr"]}