CVE-2023-20585

Publication date 16 April 2026

Last updated 26 June 2026


Ubuntu priority

Description

Insufficient checks of the RMP on host buffer access in IOMMU may allow an attacker with privileges and a compromised hypervisor to trigger an out of bounds condition without RMP checks, resulting in a potential loss of confidential guest integrity.

Read the notes from the security team

Status

Package Ubuntu Release Status
amd64-microcode 26.04 LTS resolute
Needs evaluation
25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation

Notes


rodrigo-zaiden

affects SEV FW, supported in microcode package starting from noble. AMD advisory mentions SEV release in: Milan (fam 19h model 01h): SEV FW 1.37.23 (1.55.35) Genoa (fam 19h model 11h): SEV FW 1.37.31 (1.55.49) Upstream including these versions is found in commit 13786e87: Update AMD SEV firmware to version 1.58 build 1 for AMD family 19h processors with models in the range 00h to 0fh. Update AMD SEV firmware to version 1.58 build 1 for AMD family 19h processors with models in the range 10h to 1fh. Update AMD SEV firmware to version 1.58 build 3 for AMD family 1ah processors with models in the range 00h to 0fh. AMD Security Bulletin mentions and "OS-specific update" which is not clear yet what it is about, so keeping 'needs-triage'.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
amd64-microcode

Severity score breakdown

CVSS version: CVSS v4.0

Base score 5.6 · Medium

Vector: CVSS:4.0/AV:L/AC:H/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N


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