Use-after-free in Linux kernel - CVE-2026-80775
Published: September 5, 2026
Vulnerability identifier: #VU147141
CSH Severity: Low
CVSS v4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-80775
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause memory corruption.
The vulnerability exists due to a race condition in futex_hash_allocate() when concurrently allocating the initial mm->futex_ref counter. A local user can concurrently invoke prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_SET_SLOTS) to cause memory corruption.
Exploitation requires a vfork child to invoke vfork again and then be killed with SIGKILL, causing its parent and grandchild to run concurrently while sharing the same memory map.
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-2026-80775
Install security update from vendor's repository.
kernel (Red Hat package) - update to 5.14.0-687.54.1.el9_8