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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": "2026-03-26T04:10:26.101349+00:00", "value": {"mitigation_remediation": ["Upgrade Mozilla Firefox to version 149 or later, or to the latest Firefox ESR (115.34 or later).", "Upgrade Mozilla Thunderbird to version 149 or later, or to the latest Thunderbird ESR (140.9 or later).", "If an immediate upgrade is not possible, follow the Mozilla\u2011public advisories (MFSA2026\u201120\u201124) to apply the recommended security patches as soon as they are available."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "The vulnerability affects Mozilla products Firefox, Firefox ESR (European Stable Release), and Thunderbird. Specifically, any installation of Firefox older than version 149, Firefox ESR versions older than 115.34 or 140.9, Thunderbird older than 149, or Thunderbird ESR older than 140.9 is vulnerable. These products run on multiple platforms including Windows, macOS, and Linux, exposing a broad user base such as web browsers and desktop email clients.", "description_and_impact": "A Just\u2011In\u2011Time compilation defect in the JavaScript engine\u2019s JIT component causes the runtime to generate machine code that does not match the intended semantics of JavaScript bytecode. The flaw permits an attacker to influence the execution path that the JIT compiler chooses, enabling arbitrary code execution on the affected systems. This weakness is categorized by CWE\u2011733 and CWE\u2011843 and is reflected in a CVSS score of 9.8, indicating high severity for confidentiality, integrity, and availability.", "risk_and_exploitability": "By leveraging the JIT miscompilation, an adversary could execute native code in the context of the vulnerable product, leading to full system compromise. The severity score conveys that defenders must prioritize remediation, even though the low EPSS implies that exploitation may not yet be widespread. Prompt application of updates aligned with the latest Mozilla advisories is essential."}}}}, "created": "2026-03-25T11:48:10.837578+00:00", "updated": "2026-03-26T12:20:11.724902+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr"]}