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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "matchCriteriaId": "1B590E0E-4C6F-4F2A-A0FF-9BEDA1A36D17", "versionEndExcluding": "115.33.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "matchCriteriaId": "3D8676DB-4A12-41A0-A1A5-2DED97287973", "versionEndExcluding": "148.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "matchCriteriaId": "AE16902C-47B5-438D-A4A5-770C08223931", "versionEndExcluding": "140.8.0", "versionStartIncluding": "128.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*", "matchCriteriaId": "73228A3D-A71B-497B-A5BA-412FFE9F6F37", "versionEndExcluding": "140.8.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*", "matchCriteriaId": "C5EBE90D-1996-4578-B715-605B24E66C59", "versionEndExcluding": "148.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Privilege escalation in the Messaging System component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8."}, {"lang": "es", "value": "Escalada de privilegios en el componente del sistema de mensajer\u00eda. Esta vulnerabilidad afecta a Firefox < 148, Firefox ESR < 115.33, Firefox ESR < 140.8, Thunderbird < 148, y Thunderbird < 140.8."}], "id": "CVE-2026-2777", "lastModified": "2026-04-13T15:17:24.797", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}, "published": "2026-02-24T14:16:26.123", "references": [{"source": "security@mozilla.org", "tags": ["Issue Tracking", "Permissions Required"], "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2015305"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-13/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-14/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-15/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-16/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-17/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-269"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "firefox: Privilege escalation in the Messaging System component", "id": "2442312", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2442312"}, "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-2026-2777", "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": "2026-02-24T13:33:12Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-2777\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-2777\nhttps://www.mozilla.org/security/advisories/mfsa2026-15/#CVE-2026-2777"], "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": "2026-04-15T20:15:01.331533+00:00", "value": {"mitigation_remediation": ["Upgrade to Firefox\u202f148 or later, or to the latest ESR release 115.33 or 140.8, and upgrade Thunderbird to 148 or later, or to ESR\u202f140.8.", "Review and adjust application configuration to restrict messaging component privilege usage, for example by disabling or sandboxing the component via policy if available.", "Ensure any extensions or add\u2011ons that use the messaging component are updated or removed."], "summary": {"action": "Immediate Patch", "impact": "Privilege Escalation"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox and Thunderbird, including their ESR branches, are affected. Versions before Firefox\u202f148, Firefox ESR\u202f115.33, Firefox ESR\u202f140.8, Thunderbird\u202f148, and Thunderbird ESR\u202f140.8 contain the flaw. All later releases include the fix.", "description_and_impact": "The vulnerability is a privilege escalation in the Messaging System component of Mozilla Firefox and Thunderbird. The flaw allows an attacker to perform actions at a higher privilege level within the application by exploiting the messaging component. Successful exploitation could grant unauthorized access to privileged functions or sensitive data beyond the normal user boundary. (Based on the description, it is inferred that the vulnerability involves missing access control checks.)", "risk_and_exploitability": "The CVSS base score of 9.8 indicates a critical vulnerability. The EPSS score is below 1\u202f%, indicating a low current exploitation probability, and it is not listed in CISA\u2019s KEV catalog. Based on the description, it is inferred that an attacker would need to interact with the vulnerable messaging component, likely requiring local user access or the ability to inject crafted messages; network exposure is not explicitly stated. The threat arises from the ability to elevate privileges within the application."}}}}, "created": "2026-02-25T11:39:32.020694+00:00", "updated": "2026-04-15T20:15:13.726843+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr", "mozilla$PRODUCT$thunderbird"]}