{"api_version":"1","generated_at":"2026-05-13T12:21:09+00:00","cve":"CVE-2021-27379","urls":{"html":"https://cve.report/CVE-2021-27379","api":"https://cve.report/api/cve/CVE-2021-27379.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-27379","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-27379"},"summary":{"title":"CVE-2021-27379","description":"An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access, and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush, and thus IOMMU updates were not always correct. NOTE: this issue exists because of an incomplete fix for CVE-2020-15565.","state":"PUBLIC","assigner":"cve@mitre.org","published_at":"2021-02-18 17:15:00","updated_at":"2022-05-27 17:09:00"},"problem_types":["NVD-CWE-Other"],"metrics":[],"references":[{"url":"https://xenbits.xen.org/xsa/advisory-366.html","name":"https://xenbits.xen.org/xsa/advisory-366.html","refsource":"MISC","tags":["Patch","Vendor Advisory"],"title":"XSA-366 - Xen Security Advisories","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.debian.org/security/2021/dsa-4888","name":"DSA-4888","refsource":"DEBIAN","tags":[],"title":"Debian -- Security Information -- DSA-4888-1 xen","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"http://xenbits.xen.org/xsa/advisory-366.html","name":"http://xenbits.xen.org/xsa/advisory-366.html","refsource":"CONFIRM","tags":[],"title":"XSA-366 - Xen Security Advisories","mime":"text/html","httpstatus":"200","archivestatus":"0"},{"url":"http://www.openwall.com/lists/oss-security/2021/02/23/1","name":"[oss-security] 20210223 Xen Security Advisory 366 v2 (CVE-2021-27379) - missed flush in XSA-321 backport","refsource":"MLIST","tags":["Mailing List","Third Party Advisory"],"title":"oss-security - Xen Security Advisory 366 v2 (CVE-2021-27379) - missed flush in\n XSA-321 backport","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-27379","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-27379","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2021","cve_id":"27379","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"debian","cpe5":"debian_linux","cpe6":"10.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"27379","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"xen","cpe5":"xen","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"x86","cpe13":"*"},{"cve_year":"2021","cve_id":"27379","vulnerable":"1","versionEndIncluding":"1","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"xen","cpe5":"xen","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"x86","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-27379","qid":"174927","title":"SUSE Enterprise Linux Security Update for xen (SUSE-SU-2021:1250-1)"},{"cve":"CVE-2021-27379","qid":"174928","title":"SUSE Enterprise Linux Security Update for xen (SUSE-SU-2021:1252-1)"},{"cve":"CVE-2021-27379","qid":"174929","title":"SUSE Enterprise Linux Security Update for xen (SUSE-SU-2021:1251-1)"},{"cve":"CVE-2021-27379","qid":"178530","title":"Debian Security Update for xen (DSA 4888-1)"},{"cve":"CVE-2021-27379","qid":"180504","title":"Debian Security Update for xen (CVE-2021-27379)"},{"cve":"CVE-2021-27379","qid":"377778","title":"Citrix XenServer Security Updates (CTX316324)"}]},"source_records":{"cve_program":{"CVE_data_meta":{"ASSIGNER":"cve@mitre.org","ID":"CVE-2021-27379","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"product":{"product_data":[{"product_name":"n/a","version":{"version_data":[{"version_value":"n/a"}]}}]},"vendor_name":"n/a"}]}},"data_format":"MITRE","data_type":"CVE","data_version":"4.0","description":{"description_data":[{"lang":"eng","value":"An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access, and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush, and thus IOMMU updates were not always correct. NOTE: this issue exists because of an incomplete fix for CVE-2020-15565."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"n/a"}]}]},"references":{"reference_data":[{"refsource":"CONFIRM","name":"http://xenbits.xen.org/xsa/advisory-366.html","url":"http://xenbits.xen.org/xsa/advisory-366.html"},{"url":"https://xenbits.xen.org/xsa/advisory-366.html","refsource":"MISC","name":"https://xenbits.xen.org/xsa/advisory-366.html"},{"refsource":"MLIST","name":"[oss-security] 20210223 Xen Security Advisory 366 v2 (CVE-2021-27379) - missed flush in XSA-321 backport","url":"http://www.openwall.com/lists/oss-security/2021/02/23/1"},{"refsource":"DEBIAN","name":"DSA-4888","url":"https://www.debian.org/security/2021/dsa-4888"}]}},"nvd":{"publishedDate":"2021-02-18 17:15:00","lastModifiedDate":"2022-05-27 17:09:00","problem_types":["NVD-CWE-Other"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":7.8,"baseSeverity":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:L/AC:M/Au:N/C:P/I:P/A:C","accessVector":"LOCAL","accessComplexity":"MEDIUM","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"PARTIAL","availabilityImpact":"COMPLETE","baseScore":5.9},"severity":"MEDIUM","exploitabilityScore":3.4,"impactScore":8.5,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:*","versionStartIncluding":"3.2.0","versionEndExcluding":"4.12.0","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"27379","Ordinal":"202471","Title":"CVE-2021-27379","CVE":"CVE-2021-27379","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"27379","Ordinal":"1","NoteData":"An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access, and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush, and thus IOMMU updates were not always correct. NOTE: this issue exists because of an incomplete fix for CVE-2020-15565.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"27379","Ordinal":"2","NoteData":"2021-02-18","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"27379","Ordinal":"3","NoteData":"2021-04-11","Type":"Other","Title":"Modified"}]}}}