CVE-2020-6820

{"id": "CVE-2020-6820", "cveTags": [], "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 6.8, "accessVector": "NETWORK", "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P", "authentication": "NONE", "integrityImpact": "PARTIAL", "accessComplexity": "MEDIUM", "availabilityImpact": "PARTIAL", "confidentialityImpact": "PARTIAL"}, "acInsufInfo": false, "impactScore": 6.4, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 8.6, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.2}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.2}]}, "published": "2020-04-24T16:15:13.463", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1626728", "tags": ["Issue Tracking", "Permissions Required"], "source": "security@mozilla.org"}, {"url": "https://usn.ubuntu.com/4335-1/", "tags": ["Third Party Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-11/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-14/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1626728", "tags": ["Issue Tracking", "Permissions Required"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://usn.ubuntu.com/4335-1/", "tags": ["Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-11/", "tags": ["Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-14/", "tags": ["Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-6820", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-362"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "Under certain conditions, when handling a ReadableStream, a race condition can cause a use-after-free. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Thunderbird < 68.7.0, Firefox < 74.0.1, and Firefox ESR < 68.6.1."}, {"lang": "es", "value": "Bajo determinadas condiciones, cuando se maneja un ReadableStream, una condici\u00f3n de carrera puede causar un uso de la memoria previamente liberada. Somos conscientes de los ataques dirigidos \"in the wild\" que abusan de este fallo. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 68.7.0, Firefox versiones anteriores a 74.0.1 y Firefox ESR versiones anteriores a 68.6.1."}], "lastModified": "2025-11-04T14:34:43.203", "cisaActionDue": "2022-05-03", "cisaExploitAdd": "2021-11-03", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "vulnerable": true, "matchCriteriaId": "A733A9CB-A031-4A8A-9580-8E262B6956B1", "versionEndExcluding": "68.6.1"}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "420A3EDF-5443-45D9-BF32-FA964184832A", "versionEndExcluding": "74.0.1"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CF7AEB5A-A52E-45E7-AFBF-546C351A4915", "versionEndExcluding": "68.7.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org", "cisaRequiredAction": "Apply updates per vendor instructions.", "cisaVulnerabilityName": "Mozilla Firefox And Thunderbird Use-After-Free Vulnerability"}