CVE-2021-27876

{"id": "CVE-2021-27876", "cveTags": [], "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "[email protected]", "cvssData": {"version": "2.0", "baseScore": 7.5, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:S/C:C/I:P/A:N", "authentication": "SINGLE", "integrityImpact": "PARTIAL", "accessComplexity": "LOW", "availabilityImpact": "NONE", "confidentialityImpact": "COMPLETE"}, "acInsufInfo": false, "impactScore": 7.8, "baseSeverity": "HIGH", "obtainAllPrivilege": false, "exploitabilityScore": 8.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Secondary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.8}, {"type": "Primary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.8}]}, "published": "2021-03-01T22:15:14.350", "references": [{"url": "http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "source": "[email protected]"}, {"url": "https://www.veritas.com/content/support/en_US/security/VTS21-001#issue2", "tags": ["Vendor Advisory"], "source": "[email protected]"}, {"url": "http://packetstormsecurity.com/files/168506/Veritas-Backup-Exec-Agent-Remote-Code-Execution.html", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.veritas.com/content/support/en_US/security/VTS21-001#issue2", "tags": ["Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27876", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "[email protected]", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "An issue was discovered in Veritas Backup Exec before 21.2. The communication between a client and an Agent requires successful authentication, which is typically completed over a secure TLS communication. However, due to a vulnerability in the SHA Authentication scheme, an attacker is able to gain unauthorized access and complete the authentication process. Subsequently, the client can execute data management protocol commands on the authenticated connection. By using crafted input parameters in one of these commands, an attacker can access an arbitrary file on the system using System privileges."}, {"lang": "es", "value": "Se detect\u00f3 un problema en Veritas Backup Exec versiones anteriores a 21.2. La comunicaci\u00f3n entre un cliente y un agente requiere una autenticaci\u00f3n con \u00e9xito, que generalmente se completa por medio de una comunicaci\u00f3n TLS segura. Sin embargo, debido a una vulnerabilidad en el esquema de autenticaci\u00f3n SHA, un atacante puede conseguir acceso no autorizado y completar el proceso de autenticaci\u00f3n. Posteriormente, el cliente puede ejecutar comandos de protocolo de gesti\u00f3n de datos en la conexi\u00f3n autenticada. Mediante el uso de par\u00e1metros de entrada dise\u00f1ados en uno de estos comandos, un atacante puede acceder a un archivo arbitrario en el sistema utilizando privilegios system"}], "lastModified": "2025-11-03T15:16:19.523", "cisaActionDue": "2023-04-28", "cisaExploitAdd": "2023-04-07", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:veritas:backup_exec:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2E6F2EEE-7E5A-4EA1-87F2-97C26EAE8FCC", "versionEndExcluding": "21.2"}], "operator": "OR"}]}], "sourceIdentifier": "[email protected]", "cisaRequiredAction": "Apply updates per vendor instructions.", "cisaVulnerabilityName": "Veritas Backup Exec Agent File Access Vulnerability"}