CVE-2021-26342

LowCVSS 3.3/10Last modified Jun 17, 2026

Description

In SEV guest VMs, the CPU may fail to flush the Translation Lookaside Buffer (TLB) following a particular sequence of operations that includes creation of a new virtual machine control block (VMCB). The failure to flush the TLB may cause the microcode to use stale TLB translations which may allow for disclosure of SEV guest memory contents. Users of SEV-ES/SEV-SNP guest VMs are not impacted by this vulnerability.

Metrics

CVSS 3.1 3.3/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected software

No affected versions have been published.

Timeline

Published: May 11, 2022
Last modified: Jun 17, 2026
NVD status: Modified

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