Use-after-free in Linux kernel - CVE-2026-89523

Vulnerability identifier: #VU149274

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-89523

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to use-after-free in the mt7925 Wi-Fi driver mlo_pm_work delayed work handler when the device is reset, suspended, or unregistered while the work is pending. A local user can trigger a device reset, suspension, or unregistration while the work is pending to cause a denial of service.

Pending work may send MCU commands while firmware is unavailable.

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 (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/2889e84282dda147f10b10d94cf0efd90a349c53
• https://git.kernel.org/stable/c/5be6d02837d418bc6c805b5cab1b338de6de9ca7
• https://git.kernel.org/stable/c/c5e073f2fbfd34d22099a50d96f60990799753e2

• Use-after-free in Linux kernel mt76 mt7925 driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more