CVE-2021-28697

{"id": "CVE-2021-28697", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 4.6, "accessVector": "LOCAL", "vectorString": "AV:L/AC:L/Au:N/C:P/I:P/A:P", "authentication": "NONE", "integrityImpact": "PARTIAL", "accessComplexity": "LOW", "availabilityImpact": "PARTIAL", "confidentialityImpact": "PARTIAL"}, "acInsufInfo": false, "impactScore": 6.4, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 3.9, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2021-08-27T19:15:07.673", "references": [{"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VQCFAPBNGBBAOMJZG6QBREOG5IIDZID/", "source": "security@xen.org"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZCNPSRPGFCQRYE2BI4D4Q4SCE56ANV2/", "source": "security@xen.org"}, {"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LPRVHW4J4ZCPPOHZEWP5MOJT7XDGFFPJ/", "source": "security@xen.org"}, {"url": "https://security.gentoo.org/glsa/202208-23", "tags": ["Third Party Advisory"], "source": "security@xen.org"}, {"url": "https://www.debian.org/security/2021/dsa-4977", "tags": ["Third Party Advisory"], "source": "security@xen.org"}, {"url": "https://xenbits.xenproject.org/xsa/advisory-379.txt", "tags": ["Third Party Advisory"], "source": "security@xen.org"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "grant table v2 status pages may remain accessible after de-allocation Guest get permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, get de-allocated when a guest switched (back) from v2 to v1. The freeing of such pages requires that the hypervisor know where in the guest these pages were mapped. The hypervisor tracks only one use within guest space, but racing requests from the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. Upon switching back from v2 to v1, the guest would then retain access to a page that was freed and perhaps re-used for other purposes."}, {"lang": "es", "value": "Las p\u00e1ginas de estado de grant table v2 pueden seguir siendo accesibles despu\u00e9s de la desasignaci\u00f3n. Los invitados obtienen acceso permitido a determinadas p\u00e1ginas de memoria de propiedad de Xen. La mayor\u00eda de estas p\u00e1ginas permanecen asignadas / asociadas a un hu\u00e9sped durante toda su vida. Las p\u00e1ginas de estado de grant table v2, sin embargo, se desasignan cuando un hu\u00e9sped cambia (de vuelta) de v2 a v1. La liberaci\u00f3n de estas p\u00e1ginas requiere que el hypervisor sepa en qu\u00e9 parte del hu\u00e9sped se asignaron estas p\u00e1ginas. El hypervisor rastrea s\u00f3lo un uso dentro del espacio del hu\u00e9sped, pero las peticiones de carrera del hu\u00e9sped para insertar mapeos de estas p\u00e1ginas pueden resultar en que cualquiera de ellas se mapee en m\u00faltiples ubicaciones. Al volver a cambiar de v2 a v1, el hu\u00e9sped retendr\u00eda el acceso a una p\u00e1gina que fue liberada y quiz\u00e1s reusada para otros prop\u00f3sitos."}], "lastModified": "2023-11-07T03:32:19.527", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E97F17C6-EF90-424A-99F1-9992AD7068F1", "versionEndIncluding": "4.15.0", "versionStartIncluding": "4.0.0"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E460AA51-FCDA-46B9-AE97-E6676AA5E194"}, {"criteria": "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A930E247-0B43-43CB-98FF-6CE7B8189835"}, {"criteria": "cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "80E516C0-98A4-4ADE-B69F-66A772E2BAAA"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"}], "operator": "OR"}]}], "sourceIdentifier": "security@xen.org"}