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{"bugzilla": {"description": "firefox: Undefined behavior in the DOM: Core & HTML component", "id": "2442288", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2442288"}, "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-2026-2771", "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": "2026-02-24T13:33:08Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-2771\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-2771\nhttps://www.mozilla.org/security/advisories/mfsa2026-15/#CVE-2026-2771"], "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": "2026-04-15T16:57:49.893251+00:00", "value": {"mitigation_remediation": ["Update Firefox to version\u00a0148 or later, or to the ESR 115.33 or ESR 140.8 release branches.", "Update Thunderbird to version\u00a0148 or later, or to the ESR 140.8 release branch.", "Enable automatic updates and ensure all client devices run the patched releases."], "summary": {"action": "Patch Immediately", "impact": "Memory Corruption"}, "threat_synthesis": {"affected_systems": "All versions of Mozilla Firefox and Thunderbird released before Firefox\u00a0148, Firefox ESR\u00a0115.33, Firefox ESR\u00a0140.8, Thunderbird\u00a0148, and Thunderbird ESR\u00a0140.8 are affected. The security fixes are included in those newer releases, so upgrading to those versions or later removes the vulnerability.", "description_and_impact": "This vulnerability stems from an undefined behavior in the DOM core and HTML handling components. The flaw can produce unpredictable program state or corrupt memory, which may lead to loss of integrity or other security issues. The CVE description does not explicitly state that arbitrary code execution is possible, so any claims beyond memory corruption are inferred from common exploit patterns for such faults.", "risk_and_exploitability": "The vulnerability receives a very high CVSS score of 9.8, indicating a severe potential impact. The EPSS score is below 1\u202f%, suggesting a low likelihood of exploitation at this time. It is not listed in the CISA KEV catalog, so no publicly known exploit has been reported. Based on the type of flaw and typical exploitation methods for DOM memory corruption, the likely attack vector is remote, involving a user opening malicious web content or an email attachment that triggers the bug."}}}}, "created": "2026-02-25T11:39:36.825222+00:00", "updated": "2026-04-15T17:15:10.573089+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr", "mozilla$PRODUCT$thunderbird"]}