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{"bugzilla": {"description": "firefox: Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component", "id": "2428965", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2428965"}, "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"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-0878", "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:6", "fix_state": "Out of support scope", "package_name": "firefox", "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:8", "fix_state": "Affected", "package_name": "firefox", "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"}], "public_date": "2026-01-13T13:30:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-0878\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-0878\nhttps://www.mozilla.org/security/advisories/mfsa2026-03/#CVE-2026-0878"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Important"}

{"analysis": {"en": {"generated_at": "2026-04-15T17:41:28.365937+00:00", "value": {"mitigation_remediation": ["Upgrade Mozilla Firefox to version\u00a0147 or later, or to Firefox\u00a0ESR\u00a0140.7 or later. Update Mozilla Thunderbird to version\u00a0147 or later, or to Thunderbird\u00a0ESR\u00a0140.7 or later.", "If upgrading is not immediately possible, disable WebGL in affected browsers to reduce the attack surface.", "Configure content security policies to limit or block WebGL usage for untrusted content where feasible."], "summary": {"action": "Patch", "impact": "Sandbox escape"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox and Thunderbird are impacted. Versions earlier than Firefox\u00a0147 or Firefox\u00a0ESR\u00a0140.7, and earlier than Thunderbird\u00a0147 or Thunderbird\u00a0ESR\u00a0140.7, are vulnerable. Any release prior to these thresholds remains at risk.", "description_and_impact": "The vulnerability is a sandbox escape caused by incorrect boundary conditions in the Graphics: CanvasWebGL component, which can let an attacker read or write memory outside the intended bounds. The weakness involves improper input validation and buffer management, as reflected by the identified CWEs such as CWE-119 and CWE-20.", "risk_and_exploitability": "The CVSS score of 8.0 indicates high severity, while an EPSS score of less than 1% implies a low current exploitation probability. The vulnerability is not listed in CISA\u2019s KEV catalog, meaning no widespread exploit reports exist. The likely attack vector involves an attacker supplying crafted content that triggers the CanvasWebGL component, such as a malicious web page or an email message that renders WebGL; this inference is made because the component is invoked during content rendering and the description indicates a sandbox escape. Attackers would need to supply such crafted content to achieve the exploit."}}}}, "created": "2026-01-14T11:09:10.061221+00:00", "updated": "2026-04-15T18:30:10.966497+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr"]}