Improper control of a resource through its lifetime in Linux kernel - CVE-2026-74573

Vulnerability identifier: #VU143205

CSH Severity: Low

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

CVE-ID: CVE-2026-74573

CWE-ID: CWE-664

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause stale ATC and IOTLB entries to persist.

The vulnerability exists due to improper handling of multiple stream IDs in arm_vsmmu_vsid_to_sid() in the arm-smmu-v3 iommufd code when processing vSID invalidation for a vDEVICE backed by a device with several stream IDs. A local user can trigger vSID invalidation that reaches only the first physical stream ID to cause stale ATC and IOTLB entries to persist.

The issue occurs because the mapping uses only master->streams[0] even when more than one stream ID is present.

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/0acbc621341aca4eb94d9c2f43e1ab273ff088f0
• https://git.kernel.org/stable/c/3808bab5d95ae79e333e11f6a73d178e084c645d
• https://git.kernel.org/stable/c/c3b8ee84a965058b41275069d4696f37a8b14bf6

• Improper control of a resource through its lifetime in Linux kernel arm arm-smmu-v3 driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more