Use-after-free in Linux kernel - CVE-2026-89940

Vulnerability identifier: #VU150347

CSH Severity: Low

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-89940

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to execute arbitrary code.

The vulnerability exists due to a use-after-free in the iio_dma_fence implementation when a dma fence outlives its associated iio_dmabuf_priv object. A local user can cause a dma fence to access a lock after the associated object has been freed to execute arbitrary code.

Linux kernel
Debian Linux
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)
linux (Debian 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
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/510497e31be4f241103507315a859e2085ccb081
• https://git.kernel.org/stable/c/6865d79fca17a80fbd60c12550ca9a5e0e20e0eb
• https://git.kernel.org/stable/c/8b3e221590181a8beb3735bbabf166df02c839b5
• https://git.kernel.org/stable/c/f25ec4627d935dedfb5fe83bd2c2678cdcc19611

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