8.8

CVE-2021-3656

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.

Data is provided by the National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 4.13 < 4.14.245
Linux ≫ Linux Kernel Version >= 4.15 < 4.19.205
Linux ≫ Linux Kernel Version >= 4.20 < 5.4.142
Linux ≫ Linux Kernel Version >= 5.5 < 5.10.60
Linux ≫ Linux Kernel Version >= 5.11 < 5.13.12
Linux ≫ Linux Kernel Version5.14 Update-
Linux ≫ Linux Kernel Version5.14 Updaterc1
Linux ≫ Linux Kernel Version5.14 Updaterc2
Linux ≫ Linux Kernel Version5.14 Updaterc3
Linux ≫ Linux Kernel Version5.14 Updaterc4
Linux ≫ Linux Kernel Version5.14 Updaterc5
Linux ≫ Linux Kernel Version5.14 Updaterc6
Fedoraproject ≫ Fedora Version33
Fedoraproject ≫ Fedora Version34
Redhat ≫ Software Collections Version-
   Redhat ≫ Enterprise Linux Server Version7.0
Redhat ≫ Openstack Version13
Redhat ≫ Enterprise Linux Version8.0
Redhat ≫ Enterprise Linux Eus Version8.1
Redhat ≫ Enterprise Linux Eus Version8.2
Redhat ≫ Enterprise Linux Eus Version8.4
Redhat ≫ 3scale Api Management Version2.0
   Redhat ≫ Enterprise Linux Version7.0
   Redhat ≫ Enterprise Linux Version8.0
Redhat ≫ Virtualization Host Version4.0
   Redhat ≫ Enterprise Linux Version7.0
   Redhat ≫ Enterprise Linux Version8.0
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.06% 0.175
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 8.8 2 6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
nvd@nist.gov 7.2 3.9 10
AV:L/AC:L/Au:N/C:C/I:C/A:C
CWE-862 Missing Authorization

The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

https://bugzilla.redhat.com/show_bug.cgi?id=1983988
Third Party Advisory
Issue Tracking