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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "matchCriteriaId": "DA62D95E-CB01-4586-83DB-5094116FC939", "versionEndExcluding": "140.9.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "matchCriteriaId": "02F2B82F-E997-4D5F-BBB0-237E4962555B", "versionEndExcluding": "149.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Undefined behavior in the WebRTC: Signaling component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9."}, {"lang": "es", "value": "Comportamiento indefinido en el componente de se\u00f1alizaci\u00f3n de WebRTC. Esta vulnerabilidad afecta a Firefox &lt; 149, Firefox ESR &lt; 140.9, Thunderbird &lt; 149, y Thunderbird &lt; 140.9."}], "id": "CVE-2026-4705", "lastModified": "2026-03-25T20:16:36.273", "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": "2026-03-24T13:16:06.403", "references": [{"source": "security@mozilla.org", "tags": ["Permissions Required"], "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2014873"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-20/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2026-22/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-23/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-24/"}], "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-758"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "firefox: thunderbird: Undefined behavior in the WebRTC: Signaling component", "id": "2450722", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2450722"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-475", "details": ["A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:\nUndefined behavior in the WebRTC: Signaling component"], "name": "CVE-2026-4705", "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:10", "fix_state": "Affected", "package_name": "rhel10/thunderbird-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird", "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:6", "fix_state": "Out of support scope", "package_name": "thunderbird", "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:7", "fix_state": "Out of support scope", "package_name": "thunderbird", "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:8", "fix_state": "Affected", "package_name": "thunderbird", "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"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-03-24T12:30:32Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-4705\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-4705\nhttps://www.mozilla.org/security/advisories/mfsa2026-22/#CVE-2026-4705\nhttps://www.mozilla.org/security/advisories/mfsa2026-24/#CVE-2026-4705"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,149)"}}], "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": "[0,140.9)"}}], "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"}], "analysis": {"en": {"generated_at": "2026-03-26T04:50:55.205652+00:00", "value": {"mitigation_remediation": ["Update to Firefox 149 or later, or to ESR 140.9 or later.", "Update to Thunderbird 149 or later, or to ESR 140.9 or later.", "If an update cannot be applied immediately, monitor vendor advisories for any interim guidance and consider restricting WebRTC signaling traffic to trusted origins."], "summary": {"action": "Immediate Patch", "impact": "Potential critical impact due to undefined behavior"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox versions older than 149 and the ESR branch older than 140.9, as well as Mozilla Thunderbird versions older than 149 and the ESR branch older than 140.9, are affected by this vulnerability. The same WebRTC implementation is utilized in both the browser and the mail client, meaning the impact applies to all affected installations of either product.", "description_and_impact": "The flaw is an undefined\u2011behaviour vulnerability in the WebRTC Signaling component of Mozilla products. The issue originates from code that processes signaling data, but the description does not specify the exact result of the flaw. Undefined behavior can lead to crashes, data corruption, or other unpredictable effects when the component encounters malformed input.", "risk_and_exploitability": "The CVSS score of 9.8 categorizes the vulnerability as critical, while the EPSS score indicates that active exploitation is currently uncommon. The vulnerability is not listed in CISA\u2019s Known Exploited Vulnerabilities catalog, so no publicly known exploits are documented. The attack vector is not explicitly described in the available data; based on the component\u2019s role, it is reasonable to infer that the flaw can be triggered by external entities that deliver WebRTC signaling traffic, though the precise method to achieve exploitation is not detailed."}}}}, "created": "2026-03-25T11:48:02.302854+00:00", "updated": "2026-03-26T12:20:03.766588+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr"]}