CVE-2021-46971

{"id": "CVE-2021-46971", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 3.3, "attackVector": "LOCAL", "baseSeverity": "LOW", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 1.8}]}, "published": "2024-02-27T19:04:07.343", "references": [{"url": "https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/08ef1af4de5fe7de9c6d69f1e22e51b66e385d9b", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/4348d3b5027bc3ff6336368b6c60605d4ef8e1ce", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/b246759284d6a2bc5b6f1009caeeb3abce2ec9ff", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/c7b0208ee370b89d20486fae71cd9abb759819c1", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/f5809ca4c311b71bfaba6d13f4e39eab0557895e", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "[email protected]", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix unconditional security_locked_down() call\n\nCurrently, the lockdown state is queried unconditionally, even though\nits result is used only if the PERF_SAMPLE_REGS_INTR bit is set in\nattr.sample_type. While that doesn't matter in case of the Lockdown LSM,\nit causes trouble with the SELinux's lockdown hook implementation.\n\nSELinux implements the locked_down hook with a check whether the current\ntask's type has the corresponding \"lockdown\" class permission\n(\"integrity\" or \"confidentiality\") allowed in the policy. This means\nthat calling the hook when the access control decision would be ignored\ngenerates a bogus permission check and audit record.\n\nFix this by checking sample_type first and only calling the hook when\nits result would be honored."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: perf/core: corrige la llamada incondicional a security_locked_down() Actualmente, el estado de bloqueo se consulta incondicionalmente, aunque su resultado se usa solo si el bit PERF_SAMPLE_REGS_INTR est\u00e1 establecido en attr.sample_type. Si bien eso no importa en el caso del Lockdown LSM, causa problemas con la implementaci\u00f3n del gancho de bloqueo de SELinux. SELinux implementa el gancho lock_down comprobando si el tipo de tarea actual tiene el correspondiente permiso de clase de \"bloqueo\" (\"integridad\" o \"confidencialidad\") permitido en la pol\u00edtica. Esto significa que llamar al enlace cuando se ignorar\u00eda la decisi\u00f3n de control de acceso genera una verificaci\u00f3n de permisos y un registro de auditor\u00eda falsos. Solucione este problema verificando sample_type primero y solo llamando al gancho cuando se respete su resultado."}], "lastModified": "2025-01-08T17:26:07.483", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4363F793-1288-4880-BF20-479612C7CA60", "versionEndExcluding": "5.4.117", "versionStartIncluding": "5.4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4CF5C6B5-56F0-4FA4-8D35-E62F982951FD", "versionEndExcluding": "5.10.35", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "491D6D53-3D80-40F9-8458-A0B83CCE0F64", "versionEndExcluding": "5.11.19", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CD9444EF-C1C3-4896-897A-2F3A4C436567", "versionEndExcluding": "5.12.2", "versionStartIncluding": "5.12"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}