CVE-2026-98606

A flaw was found in the Linux kernel's VirtIO GPU driver. During error handling when creating video memory resources, the driver deallocates memory without properly releasing the object from kernel memory tracking structures. A local user can exploit this vulnerability to trigger a use-after-free condition when the freed memory is subsequently accessed, leading to a Denial of Service (DoS) or potentially arbitrary code execution.

This vulnerability is rated Moderate because exploitation requires local authenticated access inside a virtual guest configured with a VirtIO GPU adapter, alongside inducing specific resource allocation failure conditions. Physical hardware systems and virtual instances not utilizing VirtIO virtualized graphics devices are not exposed. On systems configured with the device, an authenticated local attacker with direct rendering access could cause a kernel crash or potentially elevate privileges.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

--- CME Mitigation Guidance (2026-10-20) --- Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.

The highest-value action is to release the GEM object via drm_gem_object_release() before deallocating memory on virtio_gpu_vram_create() error paths in the VirtIO GPU driver: upgrade to the fixed Kernel/Kernel Rt/Kernel Ivos Qualcomm/Openshift/Ose Rhel Coreos builds, which call drm_gem_object_release() before kfree() on both error paths in virtio_gpu_vram_create(), closing crafted VirtIO GPU VRAM creation request triggering an allocation or ID allocation error. Until patched, this is only a concern on Linux systems with the VirtIO GPU driver enabled and local user access to VirtIO GPU device nodes — Non-Linux platforms and environments without the VirtIO GPU driver enabled are unaffected — so Restrict filesystem permissions on VirtIO GPU device nodes such as /dev/dri/card* and /dev/dri/renderD* to prevent untrusted local users from submitting GPU allocation ioctls. As a compensating measure, Enable runtime memory error detection such as KASAN to detect use-after-free access when the freed GEM object VMA node is traversed in the interval tree, Enable kernel SLAB freelist hardening and integrity validation to impede predictable heap exploitation following the bare kfree call, and Enforce SELinux in enforcing mode to block unauthorized process domains from opening VirtIO GPU device nodes. These controls limit blast radius and contain exploitation, but they do not fix the underlying error-handling use-after-free defect — apply the upstream patch to fully remediate.

Highest-impact CME: CME-301 SELinux (Enforcing Mode) (medium)