In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Make sure GHCB is mapped before updating Access to the GHCB is mainly in the VMGEXIT path and it is known that the GHCB will be mapped. But there are two paths where it is possible the GHCB might not be mapped. The sev_vcpu_deliver_sipi_vector() routine will update the GHCB to inform the caller of the AP Reset Hold NAE event that a SIPI has been delivered. However, if a SIPI is performed without a corresponding AP Reset Hold, then the GHCB might not be mapped (depending on the previous VMEXIT), which will result in a NULL pointer dereference. The svm_complete_emulated_msr() routine will update the GHCB to inform the caller of a RDMSR/WRMSR operation about any errors. While it is likely that the GHCB will be mapped in this situation, add a safe guard in this path to be certain a NULL pointer dereference is not encountered.
History

Wed, 11 Sep 2024 18:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-02-28T08:13:27.786Z

Updated: 2024-09-11T17:33:33.687Z

Reserved: 2024-02-27T18:42:55.952Z

Link: CVE-2021-47008

cve-icon Vulnrichment

Updated: 2024-08-04T05:24:39.477Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-02-28T09:15:38.560

Modified: 2024-02-28T14:06:45.783

Link: CVE-2021-47008

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-02-28T00:00:00Z

Links: CVE-2021-47008 - Bugzilla