CVE-2026-46065

Updated on 27 May 2026

Severity

7.8 High severity

Details

CVSS score
7.8

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved: fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an instance as part of initializing deferred I/O and remove it only after the final mapping has been closed. If the fb_info and the contained deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info to invalidate the mapping. Any access will then result in a SIGBUS signal. Fixes a long-standing problem, where a device hot-unplug happens while user space still has an active mapping of the graphics memory. The hot- unplug frees the instance of struct fb_info. Accessing the memory will operate on undefined state. A flaw was found in the Linux kernel’s framebuffer device (fbdev) deferred I/O (defio) mechanism. A local user with an active mapping of graphics memory could trigger a device hot-unplug, leading to the system accessing undefined memory. This can result in system instability or a crash, causing a Denial of Service (DoS).

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Amazon Linux 2023 Planned
Debian 12 Planned
Debian 13 Planned
Ubuntu 24.04 Planned