CVE-2021-47389: linux kernel vulnerability

CVE-2021-47389: medium vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2021-47389CVSS 5.1Linux

CVE-2021-47389: linux kernel vulnerability

CVE-2021-47389: medium vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
5.1 MEDIUM
EPSS
11.43%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: fix missing sev_decommission in sev_receive_start DECOMMISSION the current SEV context if binding an ASID fails after RECEIVE_START. Per AMD's SEV API, RECEIVE_START generates a new guest context and thus needs to be paired with DECOMMISSION: The RECEIVE_START command is the only command other than the LAUNCH_START command that generates a new guest context and guest handle. The missing DECOMMISSION can result in subsequent SEV launch failures, as the firmware leaks memory and might not able to allocate more SEV guest contexts in the future. Note, LAUNCH_START suffered the same bug, but was previously fixed by commit 934002cd660b ("KVM: SVM: Call SEV Guest Decommission if ASID binding fails").

Business impact

Successful exploitation of CVE-2021-47389, a medium vulnerability (CVSS 5.1) affecting linux kernel, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether linux kernel is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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