NULL pointer dereference in Linux kernel - CVE-2026-98928

Vulnerability identifier: #VU157582

CSH Severity: Low

CVSS v4: 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]

CVE-ID: CVE-2026-98928

CWE-ID: CWE-476

Exploitation vector: Local access

Exploit availability: No public exploit available

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.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17

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

• NULL pointer dereference in Linux kernel hyp nvhe
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more