CVE Vulnerability

CVE-2021-29657

arch/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.

6.9 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 3.4 / Impact : 10

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

Scope

7.4 /10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 1.4 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a58d9166a756a0f4a6618e4f593232593d6df134 Patch Third Party Advisory
https://bugs.chromium.org/p/project-zero/issues/detail?id=2177 Exploit Mailing List
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.12 Exploit Patch
http://packetstormsecurity.com/files/163324/KVM-nested_svm_vmrun-Double-Fetch.html Third Party Advisory VDB Entry
https://security.netapp.com/advisory/ntap-20210902-0008/ Third Party Advisory
Configurations

Configuration 1

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Information

Published : 2021-07-22 05:15

Updated : 2021-10-18 12:55

NVD link : CVE-2021-29657

Mitre link : CVE-2021-29657

Products Affected
No products.
CWE
CWE-367

CWE-416