CVE-2021-27379: Debian Linux
High severity, CVSS 7.8. EPSS: 0.4% chance of exploitation in the next 30 days.
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.
Affected products
Published 2021-02-18. Last modified 2026-06-17.