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{"bugzilla": {"description": "firefox: Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component", "id": "2442335", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2442335"}, "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-2026-2778", "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": "2026-02-24T13:33:13Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-2778\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-2778\nhttps://www.mozilla.org/security/advisories/mfsa2026-15/#CVE-2026-2778"], "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": "[0,148)"}}], "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": "[0,115.33)"}}], "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": "[0,140.8)"}}], "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": "[0,148)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,140.8)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}], "analysis": {"en": {"generated_at": "2026-04-15T15:31:21.234914+00:00", "value": {"mitigation_remediation": ["Apply the latest patched releases of Mozilla Firefox (\u2265148) or Firefox ESR (\u2265115.33 / 140.8) and Mozilla Thunderbird (\u2265148 or ESR 140.8).", "Until an upgrade is feasible, isolate the browser or mail client with least privilege, enforce a strict content\u2011security policy, and restrict or sanitize untrusted HTML content that could trigger the exploit.", "Keep the underlying operating system and any ancillary software up to date and disable or limit the use of privileged extensions or plugins that interact with DOM until the browser update is installed."], "summary": {"action": "Immediate Patch", "impact": "Remote Code Execution"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox versions up to and including 147 and all ESR builds older than 115.33 and 140.8, and Mozilla Thunderbird versions up to 147 and ESR builds older than 140.8 are affected. The exploit has been fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.", "description_and_impact": "The vulnerability allows a sandbox escape due to incorrect boundary checks in the DOM, enabling an attacker to execute arbitrary code with higher privileges than the sandbox permits. The flaw resides in the Core & HTML component and is a typical buffer overflow scenario (CWE\u2011119). An attacker could leverage this to compromise user data or system integrity once the victim processes malicious web content or an email with crafted HTML.", "risk_and_exploitability": "With a CVSS score of 10 the risk is maximal, yet the EPSS indicates a very low likelihood of exploitation (<1\u202f%). The vulnerability is not currently listed in the CISA KEV catalog. Attackers would most likely use a malicious webpage or an infected email that contains crafted HTML to trigger the sandbox escape. Because the flaw involves a buffer overflow, a successful exploitation would lift sandbox restrictions and allow arbitrary code execution on the victim\u2019s system."}}}}, "created": "2026-02-25T11:39:31.189724+00:00", "updated": "2026-04-15T17:15:10.567713+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr", "mozilla$PRODUCT$thunderbird"]}