Improper access control in Linux kernel - CVE-2026-46076
Published: May 28, 2026
Vulnerability identifier: #VU132421
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-46076
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a remote user to bypass hypercall interception controls.
The vulnerability exists due to improper access control in KVM nested SVM handling when processing VMMCALL from an L2 guest. A remote user can invoke an unhandled VMMCALL to bypass hypercall interception controls.
Exploitation requires an active nested virtualization scenario where L2 is running, L1 does not intercept VMMCALL, nested_svm_l2_tlb_flush_enabled() is true, and the hypercall is not one of the supported Hyper-V hypercalls.
How to mitigate CVE-2026-46076
Install security update from vendor's repository.