{
  "threat_severity" : "Moderate",
  "public_date" : "2020-10-20T00:00:00Z",
  "bugzilla" : {
    "description" : "xen: undue deferral of IOMMU TLB flushes (XSA-346)",
    "id" : "1891091",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=1891091"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.8",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-672",
  "details" : [ "An issue was discovered in Xen through 4.14.x allowing x86 HVM and PVH guest OS users to cause a denial of service (data corruption), cause a data leak, or possibly gain privileges because coalescing of per-page IOMMU TLB flushes is mishandled.", "A flaw was found to occur in the Xen optimization to coalesce per-page IOMMU TLB flushes. This flaw allows malicious x86 HVM and PVH guests to cause host data corruption and data leaks, resulting in a denial of service (DoS) or potential privilege escalation. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability." ],
  "statement" : "All Xen versions from 4.2 onwards are vulnerable. Red Hat Enterprise Linux 5 is not affected by this flaw, as it shipped with an older version of Xen.",
  "acknowledgement" : "Red Hat would like to thank the Xen project for reporting this issue.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 5",
    "fix_state" : "Not affected",
    "package_name" : "kernel-xen",
    "cpe" : "cpe:/o:redhat:enterprise_linux:5"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2020-27671\nhttps://nvd.nist.gov/vuln/detail/CVE-2020-27671\nhttps://xenbits.xen.org/xsa/advisory-346.html" ],
  "name" : "CVE-2020-27671",
  "mitigation" : {
    "value" : "Avoid passing through physical devices to untrusted guests. Refer to the XSA-346 advisory for additional information.",
    "lang" : "en:us"
  },
  "csaw" : false
}