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{"bugzilla": {"description": "firefox: Denial-of-service in the Libraries component in NSS", "id": "2450753", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450753"}, "csaw": false, "cvss3": {"cvss3_base_score": "3.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:N/A:N", "status": "draft"}, "cwe": "CWE-770", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nDenial-of-service in the Libraries component in NSS"], "name": "CVE-2026-4727", "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": "2026-03-24T12:30:41Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-4727\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-4727\nhttps://www.mozilla.org/security/advisories/mfsa2026-20/#CVE-2026-4727"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Low"}

{"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"}], "analysis": {"en": {"generated_at": "2026-03-25T20:52:24.896727+00:00", "value": {"mitigation_remediation": ["Update Mozilla Firefox to version 149 or later.", "Update Mozilla Thunderbird to version 149 or later.", "If an upgrade cannot be performed immediately, avoid using affected Mozilla products until a patch is applied."], "summary": {"action": "Patch Immediately", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox versions older than 149 and Mozilla Thunderbird versions older than 149 are affected. All newer releases of these products are not vulnerable.", "description_and_impact": "The NSS Libraries component, used by Mozilla email and browser clients, contains a flaw that can be exercised to make the library stop responding or crash. This causes the host application\u2014Firefox or Thunderbird\u2014to become unusable or terminate, resulting in a denial of service. The weakness is reflected by CWE-400 and CWE-770 and does not lead to data disclosure or code execution.", "risk_and_exploitability": "The CVSS score of 7.5 marks the issue as high severity. The EPSS score of less than 1% indicates a low probability of current exploitation, and the vulnerability is not listed in the CISA KEV catalog. The description does not provide a clear attacker capability, but because the fault resides in a local library component, the likely attack vector is local execution or privilege elevation. Therefore a compromised or privileged user would be required to trigger the denial of service."}}}}, "created": "2026-03-25T11:47:48.097680+00:00", "updated": "2026-03-25T21:27:47.589588+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}