Race condition in Linux kernel - CVE-2026-98552

Vulnerability identifier: #VU156855

CSH Severity: Low

CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98552

CWE-ID: CWE-362

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to leak kernel resources, potentially causing a denial of service.

The vulnerability exists due to a race condition in the Linux kernel perf context attachment logic when global and non-global context attachments occur concurrently. A local user can trigger competing attachment operations that increment a reference count without setting the global flag, causing subsequent global detachment to skip the corresponding task context cleanup and potentially exhaust kernel resources.

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/23250517cd475367653f1e99396967f54c6f1b7c
• https://git.kernel.org/stable/c/5286d4eb5cd7e10d7d93c3cc596e18bc8ad80f72
• https://git.kernel.org/stable/c/cca4980630b3c7a85f53cb43c6018184ce5d4e37

• Race condition in Linux kernel events
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more