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{"bugzilla": {"description": "firefox: Use-after-free in the WebRTC component", "id": "2460095", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460095"}, "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. The Mozilla Foundation's Security Advisory describes the following issue:\nUse-after-free in the WebRTC component"], "name": "CVE-2026-6747", "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": "2026-04-21T12:40:45Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-6747\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-6747\nhttps://www.mozilla.org/security/advisories/mfsa2026-30/#CVE-2026-6747\nhttps://www.mozilla.org/security/advisories/mfsa2026-32/#CVE-2026-6747"], "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": "unaffected", "versions": {"scheme": "generic", "value": "[140.10,140.*]"}}, {"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": "2026-04-22T08:06:43.228283+00:00", "value": {"mitigation_remediation": ["Update to the latest Firefox release (150 or newer) or the ESR 140.10 patch to address the flaw.", "Update to the latest Thunderbird release (150 or newer) or the ESR 140.10 patch to address the flaw.", "If an immediate update is not feasible, disable WebRTC globally via browser settings or group policy to prevent the vulnerable code path from executing."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox installations running any version before the security fixes delivered in Firefox\u202f150 and the ESR release 140.10 remain vulnerable; this includes all earlier consumer releases and older ESR branches such as 140.9 and prior. Mozilla Thunderbird installations running any version before the security fixes delivered in Thunderbird\u202f150 and the ESR release 140.10 also remain vulnerable.", "description_and_impact": "Use\u2011after\u2011free in the WebRTC component allows memory corruption when a client processes malformed WebRTC packets. The flaw could enable an attacker to execute arbitrary code or crash the browser. The vulnerability was addressed in Firefox\u202f150, Firefox ESR\u202f140.10, Thunderbird\u202f150, and Thunderbird\u202f140.10.", "risk_and_exploitability": "The vulnerability carries a CVSS score of 7.5. EPSS information is not available, and the issue is not listed in CISA KEV. Based on the description, it is inferred that attackers would need to trigger a WebRTC session with crafted data, a scenario that could arise from malicious web content or compromised network traffic. Although no publicly available exploits are documented, the memory\u2011corruption nature of the flaw presents a substantial risk of remote code execution."}}}}, "created": "2026-04-21T17:15:25.104265+00:00", "updated": "2026-04-22T08:15:05.752322+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}