CVE - CVE-2021-3656

CVE-ID
CVE-2021-3656	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "virt_ext" field, this issue could allow a malicious L1 to disable both VMLOAD/VMSAVE intercepts and VLS (Virtual VMLOAD/VMSAVE) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://bugzilla.redhat.com/show_bug.cgi?id=1983988 URL:https://bugzilla.redhat.com/show_bug.cgi?id=1983988 MISC:https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc URL:https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc MISC:https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc URL:https://github.com/torvalds/linux/commit/c7dfa4009965a9b2d7b329ee970eb8da0d32f0bc MISC:https://www.openwall.com/lists/oss-security/2021/08/16/1 URL:https://www.openwall.com/lists/oss-security/2021/08/16/1
Assigning CNA
Red Hat, Inc.
Date Record Created
20210721	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20210721)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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