CVE-2020-12443

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{"affected": [{"affectedData": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "source": "cve@mitre.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:*", "matchCriteriaId": "D85D343D-D25C-4B39-A011-2E4987CECD52", "versionEndExcluding": "2.2.6", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "BigBlueButton before 2.2.6 allows remote attackers to read arbitrary files because the presfilename (lowercase) value can be a .pdf filename while the presFilename (mixed case) value has a ../ sequence. This can be leveraged for privilege escalation via a directory traversal to bigbluebutton.properties. NOTE: this issue exists because of an ineffective mitigation to CVE-2020-12112 in which there was an attempted fix within an NGINX configuration file, without considering that the relevant part of NGINX is case-insensitive."}, {"lang": "es", "value": "BigBlueButton versiones anteriores a 2.2.6, permite a atacantes remotos leer archivos arbitrarios porque el valor de presfilename (min\u00fasculas) puede ser un nombre de archivo .pdf mientras que el valor de presFilename (may\u00fasculas y min\u00fasculas) presenta una secuencia ../. Esto puede ser aprovechado para una escalada de privilegios por medio de un salto de directorio en bigbluebutton.properties. NOTA: este problema existe debido a una mitigaci\u00f3n ineficaz de CVE-2020-12112 en la que se intent\u00f3 corregir dentro de un archivo de configuraci\u00f3n NGINX, sin considerar que la parte relevante de NGINX no distingue entre may\u00fasculas y min\u00fasculas."}], "id": "CVE-2020-12443", "lastModified": "2026-06-17T02:51:50.060", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "HIGH", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "PARTIAL", "baseScore": 7.5, "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 6.4, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "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"}]}, "published": "2020-04-29T02:15:11.467", "references": [{"source": "cve@mitre.org", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463"}, {"source": "cve@mitre.org", "tags": ["Exploit", "Third Party Advisory"], "url": "https://github.com/mclab-hbrs/BBB-POC"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory"], "url": "https://github.com/mclab-hbrs/BBB-POC"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-22"}], "source": "nvd@nist.gov", "type": "Primary"}]}

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