Quick answers
- Is CVE-2026-40668 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-40668 being exploited in the wild.
- How severe is CVE-2026-40668?
- Informational severity, published 10 November 2026.
- Which products and versions are affected?
- AMD Secure Encrypted Virtualization firmware.
- Is there a fix for CVE-2026-40668?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-40668 attacked?
- It is attacked with local access, in device firmware.
- Am I affected by CVE-2026-40668?
- Check whether you run Amd Secure Encrypted Virtualization firmware. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An authentication bypass vulnerability in AMD SEV firmware allows a malicious hypervisor to spoof its identity and request attestation reports for VMPL 0, which should be restricted to the highest privilege level only. The flaw is in the attestation request validation logic, where insufficient verification of the requester's privilege level permits unauthorized access to sensitive reports. A fix is available in updated SEV firmware versions.
Affected products
- AMD Secure Encrypted Virtualization firmware
Timeline
- 2026-11-10: disclosed