CVE-2021-47035
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Remove WO permissions on second-level paging entries When the first level page table is used for IOVA translation, it only supports Read-Only and Read-Write permissions.
Does this matter?
Lower severity and a low EPSS score (0.26%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Remove WO permissions on second-level paging entries When the first level page table is used for IOVA translation, it only supports Read-Only and Read-Write permissions. The Write-Only permission is not supported as the PRESENT bit (implying Read permission) should always set. When using second level, we still give separate permissions that allows WriteOnly which seems inconsistent and awkward. We want to have consistent behavior. After moving to 1st level, we don't want things to work sometimes, and break if we use 2nd level for the same mappings. Hence remove this configuration.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.26% probability · 17th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/25faff78138933244c678c7fc78f7c0340fa04a0Patch
- https://git.kernel.org/stable/c/66c24699f266ff310381a9552d3576eea8ad6e20Patch
- https://git.kernel.org/stable/c/89bd620798704a8805fc9db0d71d7f812cf5b3d2Patch
- https://git.kernel.org/stable/c/eea53c5816889ee8b64544fa2e9311a81184ff9cPatch
- https://git.kernel.org/stable/c/25faff78138933244c678c7fc78f7c0340fa04a0Patch
- https://git.kernel.org/stable/c/66c24699f266ff310381a9552d3576eea8ad6e20Patch
- https://git.kernel.org/stable/c/89bd620798704a8805fc9db0d71d7f812cf5b3d2Patch
- https://git.kernel.org/stable/c/c848416cc05afc1589edba04fe00b85c2f797ee3Patch
- https://git.kernel.org/stable/c/eea53c5816889ee8b64544fa2e9311a81184ff9cPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.