SB20261023242 - NULL pointer dereference in Linux kernel hyp nvhe

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-98928)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local privileged user to cause a denial of service through a NULL pointer dereference in the hypervisor.

The vulnerability exists due to inconsistent validation of SVE feature indicators in the arm64 KVM function pkvm_init_features_from_host() when initializing guest CPU features from host-supplied state. A local privileged user can set KVM_ARCH_FLAG_GUEST_HAS_SVE without setting KVM_ARM_VCPU_SVE, causing the world switch to load guest SVE state through a NULL sve_state pointer and potentially crash the hypervisor.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/4efda204087145d40a84344edec7e9d3885ad3ab
• https://git.kernel.org/stable/c/4f16c5fc8dc4c5596e3777ab9f449a54e3f85fd5
• https://git.kernel.org/stable/c/7b5e99d286747b6b5b583b8efcd06bdbdd94b229