{"id":"CVE-2021-27379","aliases":["DEBIAN-CVE-2021-27379","DSA-4888-1","EUVD-2021-14134","GHSA-f444-f4gw-jhg6","SUSE-SU-2021:1250-1","SUSE-SU-2021:1251-1","SUSE-SU-2021:1252-1","SUSE-SU-2021:1268-1","UBUNTU-CVE-2021-27379"],"status":"published","title":"An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve...","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. 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Advisory","fix"]},{"url":"https://xenbits.xen.org/xsa/advisory-366.html","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory","fix","report"]},{"url":"http://www.openwall.com/lists/oss-security/2021/02/23/1","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4888","tags":["vendor-advisory","x_refsource_DEBIAN","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-27379"},{"url":"https://github.com/advisories/GHSA-f444-f4gw-jhg6"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-27379","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2021/suse-su-20211250-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1178591","tags":["report"]},{"url":"https://bugzilla.suse.com/1182431","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2021-27379","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2021/suse-su-20211251-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1182846","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2021-20257","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2021/suse-su-20211252-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2021/suse-su-20211268-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1182155","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-27379","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-27379","tags":["report"]}],"sources":{"cve":[{"id":"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.","status":"published","published":"2021-02-18T15:05:25Z","modified":"2024-08-03T20:48:16.398Z","updated_at":"2026-11-02T14:33:04.360272Z"}],"euvd":[{"id":"EUVD-2021-14134","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.","status":"published","published":"2021-02-18T15:05:25Z","modified":"2024-08-03T20:48:16Z","updated_at":"2026-11-03T03:24:49.368497Z"}],"ghsa":[{"id":"GHSA-f444-f4gw-jhg6","title":"An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve...","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.","status":"published","published":"2022-05-24T17:42:38Z","modified":"2023-01-29T05:05:29Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-269"],"updated_at":"2026-11-02T14:45:48.396935Z"}],"nvd":[{"id":"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.","status":"published","published":"2021-02-18T17:15:15.867Z","modified":"2026-06-17T03:44:44.44Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5.9,"vector":"AV:L/AC:M/Au:N/C:P/I:P/A:C","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:06:50.031227Z"}],"osv":[{"id":"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.","status":"published","published":"2021-02-18T17:15:15.867Z","modified":"2026-03-15T22:39:57.065704Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:18.778776Z"},{"id":"DEBIAN-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.","status":"published","published":"2021-02-18T17:15:15.867Z","modified":"2026-10-23T18:03:59.137383233Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:34.94143Z"},{"id":"UBUNTU-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.","status":"published","published":"2021-02-18T17:15:00Z","modified":"2026-10-17T12:57:12.699752739Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:26.779273Z"},{"id":"DSA-4888-1","title":"xen - security update","status":"published","published":"2021-04-10T00:00:00Z","modified":"2026-03-09T02:09:54.200097Z","updated_at":"2026-11-02T15:46:17.19998Z"},{"id":"SUSE-SU-2021:1250-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2021-27379: Fixed an issue where entries in the IOMMU were not being updated \n  under certain circumstances due to improper backport of XSA-321 (XSA-366, bsc#1182431)\n","status":"published","published":"2021-04-19T06:58:03Z","modified":"2026-02-04T02:51:42.343321Z","updated_at":"2026-11-02T15:53:49.138643Z"},{"id":"SUSE-SU-2021:1251-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2021-27379: Fixed an issue where entries in the IOMMU were not being updated under certain circumstances due to improper backport of XSA-321 (XSA-366, bsc#1182431)\n- CVE-2021-20257: Fixed an infinite loop in the e1000 NIC emulator (bsc#1182846)\n","status":"published","published":"2021-04-19T06:58:14Z","modified":"2026-02-04T02:29:08.656609Z","updated_at":"2026-11-02T15:53:49.138643Z"},{"id":"SUSE-SU-2021:1252-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2021-20257: xen: infinite loop issue in the e1000 NIC emulator (bsc#1182846).\n- CVE-2021-27379: Fixed an issue where entries in the IOMMU were not being updated \n  under certain circumstances due to improper backport of XSA-321 (XSA-366, bsc#1182431).\n","status":"published","published":"2021-04-19T06:58:25Z","modified":"2026-02-04T02:20:47.764609Z","updated_at":"2026-11-02T15:53:49.138643Z"},{"id":"SUSE-SU-2021:1268-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2021-27379: Fixed an issue where entries in the IOMMU were not being updated under certain circumstances due to improper backport of XSA-321 (XSA-366, bsc#1182431)\t  \n- Fixed  an issue where xenstored was crashing with segfault (bsc#1182155).  \n","status":"published","published":"2021-04-20T08:55:04Z","modified":"2026-02-04T04:12:38.628819Z","updated_at":"2026-11-02T15:53:49.138643Z"}]}}