01 Record

CVE-2026-40668

Authentication bypass by spoofing in AMD Secure Encrypted Virtualization (SEV) firmware could allow a malicious hypervisor to request attestation reports for VMPL 0.

MediumPUBLISHEDCNA: AMD

CNA base score4.6 CVSS v4.0CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

View raw JSON

02 Description

Authentication bypass by spoofing in AMD Secure Encrypted Virtualization (SEV) firmware could allow a malicious hypervisor to request attestation reports for VMPL 0.

03 Exploitation and scoring

Exploitation: Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
SSVC decision: Not assessed by CISA
EPSS probability: Not scored by EPSS
EPSS percentile: Not scored by EPSS
NVD base score: The NVD has published no score for this record
NVD CVSS vector: No NVD score to derive
NVD analysis status: Not recorded
Red Hat severity: No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.