Use-after-free in Linux kernel - CVE-2026-23415
Published: April 3, 2026
Vulnerability identifier: #VU124859
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-2026-23415
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in __futex_key_to_node() when processing futex operations during a race with vma policy replacement. A local user can trigger concurrent futex activity and memory policy changes to cause a denial of service.
The issue is caused by a race between futex_key_to_node_opt() and vma_replace_policy() that leads to a use-after-free read of mpol->mode from a freed mempolicy pointer.
Affected software
Linux kernel
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
kernel (Red Hat package)
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
kernel (Red Hat package)
How to mitigate CVE-2026-23415
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - update to 5.14.0-687.36.1.el9_8
kernel (Red Hat package) - update to 5.14.0-687.36.1.el9_8