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{}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[115.35,116.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.10,141.0.0)"}}, {"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": "2026-04-21T23:00:51.138957+00:00", "value": {"mitigation_remediation": ["Apply a vendor\u2011supplied patch by upgrading to Firefox 150, Firefox ESR 115.35, or Firefox ESR 140.10.", "For environments unable to update immediately, restrict or disable JavaScript execution on untrusted sites to reduce the attack surface.", "Deploy monitoring tools to detect abnormal memory activity or crashes that may indicate exploitation attempts."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox is affected. The vulnerability was fixed in Firefox 150, Firefox ESR 115.35, and Firefox ESR 140.10, implying that all earlier releases before those version numbers are vulnerable. The list of products is limited to the Mozilla Firefox browser; no other vendors or products are mentioned.", "description_and_impact": "The vulnerability is a use\u2011after\u2011free flaw in the JavaScript Engine component of Mozilla Firefox. This type of memory corruption can allow an attacker to execute arbitrary code, potentially compromising confidentiality, integrity, and availability of the affected system. No further details about the specific attack path are provided, but the flaw\u2019s nature suggests severe consequences if exploited.", "risk_and_exploitability": "The CVSS score is not disclosed, and the EPSS score is not available. The vulnerability is not listed in CISA\u2019s KEV catalog, indicating there is no public record of current exploitation for this issue. Nonetheless, use\u2011after\u2011free vulnerabilities in web browsers are high\u2011risk due to their ability to enable arbitrary code execution, especially when enabled scripts come from untrusted web content. The lack of publicly available exploit metrics does not reduce the potential impact; it merely reflects that the vulnerability is not yet observed in the wild."}}}}, "created": "2026-04-21T16:45:15.077971+00:00", "updated": "2026-04-21T23:15:03.113173+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"], "weaknesses": ["CWE-416"]}