CVE-2021-47389
KVM SVM SEV Guest Context Decommission Vulnerability
Description
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").
INFO
Published Date :
May 21, 2024, 3:15 p.m.
Last Modified :
April 2, 2025, 2:52 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
2.5
Exploitability Score :
2.5
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47389.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-47389 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47389 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Apr. 02, 2025
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.13 up to (excluding) 5.14.10 Added Reference Type CVE: https://git.kernel.org/stable/c/efd7866e114dcb44f86d151e843f8276b7efbc67 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/efd7866e114dcb44f86d151e843f8276b7efbc67 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/f1815e0aa770f2127c5df31eb5c2f0e37b60fa77 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/f1815e0aa770f2127c5df31eb5c2f0e37b60fa77 Types: Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/efd7866e114dcb44f86d151e843f8276b7efbc67 Added Reference https://git.kernel.org/stable/c/f1815e0aa770f2127c5df31eb5c2f0e37b60fa77 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 09, 2024
Action Type Old Value New Value Added CWE CISA-ADP CWE-772 Removed CWE CISA-ADP CWE-400 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 03, 2024
Action Type Old Value New Value Added CWE CISA-ADP CWE-400 Added CVSS V3.1 CISA-ADP AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 21, 2024
Action Type Old Value New Value Added Description 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"). Added Reference kernel.org https://git.kernel.org/stable/c/efd7866e114dcb44f86d151e843f8276b7efbc67 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/f1815e0aa770f2127c5df31eb5c2f0e37b60fa77 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47389 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47389
weaknesses.