{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-04-22T21:20:05.077","vulnerabilities":[{"cve":{"id":"CVE-2021-28701","sourceIdentifier":"security@xen.org","published":"2021-09-08T14:15:08.547","lastModified":"2024-11-21T06:00:10.450","vulnStatus":"Modified","cveTags":[],"descriptions":[{"lang":"en","value":"Another race in XENMAPSPACE_grant_table handling Guests are 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, are de-allocated when a guest switches (back) from v2 to v1. Freeing such pages requires that the hypervisor enforce that no parallel request can result in the addition of a mapping of such a page to a guest. That enforcement was missing, allowing guests to retain access to pages that were freed and perhaps re-used for other purposes. Unfortunately, when XSA-379 was being prepared, this similar issue was not noticed."},{"lang":"es","value":"Otra carrera en el manejo de la función XENMAPSPACE_grant_table de los Huéspedes, se les permite el acceso a determinadas páginas de memoria propiedad de Xen. La mayoría de estas páginas permanecen asignadas / asociadas a un huésped durante toda su vida. Las páginas de estado de la tabla Grant v2, sin embargo, se desasignan cuando un huésped cambia (de nuevo) de v2 a v1. Una liberación de dichas páginas requiere que el hipervisor haga cumplir que ninguna petición paralela pueda resultar en la adición de un mapeo de dicha página a un huésped. Esta aplicación no existía, permitiendo a los huéspedes mantener el acceso a las páginas liberadas y quizás reusarlas para otros fines. Desafortunadamente, cuando fue preparada la XSA-379, no se advirtió este problema similar"}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"HIGH","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.1,"impactScore":6.0}],"cvssMetricV2":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"2.0","vectorString":"AV:L/AC:M/Au:N/C:P/I:P/A:P","baseScore":4.4,"accessVector":"LOCAL","accessComplexity":"MEDIUM","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"PARTIAL","availabilityImpact":"PARTIAL"},"baseSeverity":"MEDIUM","exploitabilityScore":3.4,"impactScore":6.4,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-362"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*","versionStartIncluding":"4.0.0","matchCriteriaId":"3E095C1C-0DC6-4380-9333-477B13273E9E"}]}]},{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*","matchCriteriaId":"FA6FEEC2-9F11-4643-8827-749718254FED"}]}]},{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*","matchCriteriaId":"E460AA51-FCDA-46B9-AE97-E6676AA5E194"},{"vulnerable":true,"criteria":"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*","matchCriteriaId":"A930E247-0B43-43CB-98FF-6CE7B8189835"},{"vulnerable":true,"criteria":"cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*","matchCriteriaId":"80E516C0-98A4-4ADE-B69F-66A772E2BAAA"}]}]}],"references":[{"url":"http://www.openwall.com/lists/oss-security/2021/09/08/2","source":"security@xen.org","tags":["Mailing List","Third Party Advisory"]},{"url":"http://xenbits.xen.org/xsa/advisory-384.html","source":"security@xen.org","tags":["Vendor Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3HEHUIUWSSMCQGQY3GWX4J2SZGYP5W2Z/","source":"security@xen.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEHZLIR5DFYYQBH55AERWHLO54OFU42C/","source":"security@xen.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L4MI3MQAPGILCLXBGQWPZHGE3ALSO4ZU/","source":"security@xen.org"},{"url":"https://security.gentoo.org/glsa/202208-23","source":"security@xen.org","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4977","source":"security@xen.org","tags":["Third Party Advisory"]},{"url":"https://xenbits.xenproject.org/xsa/advisory-384.txt","source":"security@xen.org","tags":["Vendor Advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2021/09/08/2","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Mailing List","Third Party Advisory"]},{"url":"http://xenbits.xen.org/xsa/advisory-384.html","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Vendor Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3HEHUIUWSSMCQGQY3GWX4J2SZGYP5W2Z/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEHZLIR5DFYYQBH55AERWHLO54OFU42C/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L4MI3MQAPGILCLXBGQWPZHGE3ALSO4ZU/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202208-23","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4977","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Third Party Advisory"]},{"url":"https://xenbits.xenproject.org/xsa/advisory-384.txt","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Vendor Advisory"]}]}}]}