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{"bugzilla": {"description": "firefox: thunderbird: Use-after-free in the Layout: Text and Fonts component", "id": "2450740", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450740"}, "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 and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:\nUse-after-free in the Layout: Text and Fonts component"], "name": "CVE-2026-4696", "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": "2026-03-24T12:30:26Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-4696\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-4696\nhttps://www.mozilla.org/security/advisories/mfsa2026-22/#CVE-2026-4696\nhttps://www.mozilla.org/security/advisories/mfsa2026-24/#CVE-2026-4696"], "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": "2026-04-13T15:50:42.243755+00:00", "value": {"mitigation_remediation": ["Update Firefox to version 149 or later, or to ESR 115.34 or 140.9 and higher", "Update Thunderbird to version 149 or to ESR 140.9 and higher", "Verify that the system is running a patched version after installation", "Monitor official security advisories for any new updates or workarounds"], "summary": {"action": "Immediate Patch", "impact": "Memory corruption with potential remote code execution"}, "threat_synthesis": {"affected_systems": "The vulnerability affects Mozilla Firefox and its ESR releases, as well as Mozilla Thunderbird. All versions prior to Firefox 149, Firefox ESR 115.34 and 140.9, Thunderbird 149, and Thunderbird 140.9 are susceptible.", "description_and_impact": "A use\u2011after\u2011free flaw exists in the Layout: Text and Fonts component. When triggered, the browser or email client may free an object before all references to it are released. This can allow an attacker to corrupt memory, leading to crashes or the execution of injected code, thereby compromising the confidentiality, integrity, or availability of the affected system.", "risk_and_exploitability": "With a CVSS score of 9.8 the flaw is considered critical, yet the EPSS score is below 1% and it is not listed in the CISA KEV catalog, indicating a low likelihood of exploitation at this time. The most plausible attack vector would be a crafted web page or email that triggers the text and font rendering engine, which would require the victim to view or open the malicious content. No public exploits are currently documented, but the high severity warrants immediate action."}}}}, "created": "2026-03-25T11:48:12.665577+00:00", "updated": "2026-04-14T16:43:33.525727+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr"]}