Use-after-free in Linux kernel - CVE-2026-98260

Vulnerability identifier: #VU153756

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98260

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 POSIX CPU timer cleanup during process execution and termination when a non-leader thread executes a program and a subsequent failure leaves a freed timer node queued. A local user can create and arm a per-thread CPU timer and trigger an execution failure after the thread ID exchange, followed by task reaping, to cause a denial of service.

The affected timer functionality requires CONFIG_POSIX_TIMERS to be enabled.

Linux kernel
Debian Linux
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
kernel (Red Hat package)
kernel-rt (Red Hat package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - addressed in versions 5.14.0-284.198.1.el9_2, 5.14.0-427.156.1.el9_4, 5.14.0-570.149.1.el9_6, 6.12.0-55.111.1.el10_0
kernel-rt (Red Hat package) - update to 5.14.0-284.198.1.rt14.483.el9_2
linux (Debian package) - update to 6.12.113-1

• https://git.kernel.org/stable/c/6f1977cea3e85cd8ab55fb337d3e1725fe61d1ce
• https://git.kernel.org/stable/c/75aa08b93c65766040f9ca99f41ac85ad22596b6
• https://git.kernel.org/stable/c/acb03d3881818581052924a9bbbe92b8741ed448
• https://git.kernel.org/stable/c/d602877baf36c43c788a5f472c977e0be414029f
• https://git.kernel.org/stable/c/d9ae467e617ca29b825493a362bf0d75ad5f4ac3

• Use-after-free in Linux kernel fs
• Red Hat Enterprise Linux 10 update for kernel
• Red Hat Enterprise Linux 9 update for kernel
• Red Hat Enterprise Linux 9 update for kernel-rt
• Red Hat Enterprise Linux 9 update for kernel
• Red Hat Enterprise Linux 9 update for kernel
• Debian update for linux