7.4
CVE-2021-29657
- EPSS 0.04%
- Published 22.07.2021 17:15:09
- Last modified 21.11.2024 06:01:35
- Source cve@mitre.org
- CVE-Watchlists
- Open
Loginarch/x86/kvm/svm/nested.c in the Linux kernel before 5.11.12 has a use-after-free in which an AMD KVM guest can bypass access control on host OS MSRs when there are nested guests, aka CID-a58d9166a756. This occurs because of a TOCTOU race condition associated with a VMCB12 double fetch in nested_svm_vmrun.
Data is provided by the National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 5.10 < 5.10.28
Linux ≫ Linux Kernel Version >= 5.11 < 5.11.12
| Type | Source | Score | Percentile |
|---|---|---|---|
| EPSS | FIRST.org | 0.04% | 0.097 |
| Source | Base Score | Exploit Score | Impact Score | Vector string |
|---|---|---|---|---|
| nvd@nist.gov | 7.4 | 1.4 | 5.9 |
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
|
| nvd@nist.gov | 6.9 | 3.4 | 10 |
AV:L/AC:M/Au:N/C:C/I:C/A:C
|
CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state.
CWE-416 Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.