CVE-2021-3656
Severity
8.8HIGH
EPSS
0.1%
top 78.17%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedMar 4
Latest updateMar 8
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 cra…
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitability: 2.0 | Impact: 6.0
Affected Packages28 packages
Also affects: Fedora 33, 34, Enterprise Linux 8.0, 8.1, 8.2, 8.4, 7.0, 7, 8, 7.6, 7.7
Patches
🔴Vulnerability Details
12📋Vendor Advisories
11Microsoft▶
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 nes↗2022-03-08