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 "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) for the L2 guest. As a result, the L2 guest would be allowed to 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. Upstream fix: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=0f923e07124df069ba68d8bb12324398f4b6b709
This bug dates way back to kernel 2.6.30 where it was first introduced via commit: https://github.com/torvalds/linux/commit/3d6368ef580a
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1995451]
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2021:3547 https://access.redhat.com/errata/RHSA-2021:3547
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2021:3548 https://access.redhat.com/errata/RHSA-2021:3548
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2021-3653
This issue has been addressed in the following products: Red Hat Enterprise Linux 8.1 Extended Update Support Via RHSA-2021:3676 https://access.redhat.com/errata/RHSA-2021:3676
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.2 Advanced Update Support Via RHSA-2021:81932 https://access.redhat.com/errata/RHSA-2021:81932
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.6 Advanced Update Support Red Hat Enterprise Linux 7.6 Update Services for SAP Solutions Red Hat Enterprise Linux 7.6 Telco Extended Update Support Via RHSA-2021:3812 https://access.redhat.com/errata/RHSA-2021:3812
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2021:3801 https://access.redhat.com/errata/RHSA-2021:3801
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2021:3802 https://access.redhat.com/errata/RHSA-2021:3802
This issue has been addressed in the following products: Red Hat Enterprise Linux 8.2 Extended Update Support Via RHSA-2021:3909 https://access.redhat.com/errata/RHSA-2021:3909
This issue has been addressed in the following products: Red Hat Enterprise Linux 8.2 Extended Update Support Via RHSA-2021:3904 https://access.redhat.com/errata/RHSA-2021:3904
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.7 Advanced Update Support Red Hat Enterprise Linux 7.7 Update Services for SAP Solutions Red Hat Enterprise Linux 7.7 Telco Extended Update Support Via RHSA-2021:3987 https://access.redhat.com/errata/RHSA-2021:3987
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.4 Advanced Update Support Via RHSA-2021:4692 https://access.redhat.com/errata/RHSA-2021:4692
This issue has been addressed in the following products: Red Hat Enterprise Linux 7.3 Advanced Update Support Via RHSA-2021:4768 https://access.redhat.com/errata/RHSA-2021:4768