CVE-2021-29657

Description

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.

Weakness classification

• nvd@nist.gov: CWE-367

Primary references

• cve@mitre.org — Third Party Advisory, VDB Entry
• cve@mitre.org — Exploit, Mailing List, Patch, Third Party Advisory
• cve@mitre.org — Exploit, Patch, Vendor Advisory
• cve@mitre.org — Patch, Third Party Advisory
• cve@mitre.org — Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory, VDB Entry
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Mailing List, Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Exploit, Patch, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory