Missing Release of Resource after Effective Lifetime in Linux kernel - CVE-2026-89447

Vulnerability identifier: #VU149358

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-2026-89447

CWE-ID: CWE-772

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 improper resource release in iommufd_access_notify_unmap() when handling unmap notifications for internal accesses. A local user can trigger unmap handling involving internal accesses to cause a denial of service.

Internal accesses do not have an external unmap callback.

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/0dbcdf4473a614adbd732d567c9b39ac0e040e0c
• https://git.kernel.org/stable/c/436189ee4bb2c7c993b945d68570dd38c3e4349e
• https://git.kernel.org/stable/c/50a66a63d1c841ae6b28a4551f642c1bba4c9529

• Missing Release of Resource after Effective Lifetime in Linux kernel iommu iommufd driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more