CVE-2026-64560

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 6.18.41 Linux kernel versions prior to 6.12.100 Linux kernel versions prior to 6.6.147 Linux kernel versions prior to 6.1.180 Linux kernel versions prior to 5.15.213 Linux kernel versions prior to 5.10.262

Description A use-after-free (UAF) issue exists in the posix-cpu-timers subsystem of the Linux kernel. The problem occurs during a race condition involving a non-leader exec() call, where a task lookup may return an old leader that is subsequently released. This can lead to the free posix timer() function freeing a timer object that is still enqueued in the signal queue. Consequently, subsequent operations such as run posix cpu timers() or other timer queue modifications may access the freed memory. Similar issues affect posix cpu timer set() and posix cpu timer rearm(), the latter of which may fail to rearm the timer, causing it to stop expiring. Additionally, on weakly ordered architectures, a lack of proper memory ordering in posix cpu timer del() could lead to false positive warnings during task exit.

Recommendations Update the Linux kernel to version 6.18.41 or newer. Update the Linux kernel to version 6.12.100 or newer. Update the Linux kernel to version 6.6.147 or newer. Update the Linux kernel to version 6.1.180 or newer. Update the Linux kernel to version 5.15.213 or newer. Update the Linux kernel to version 5.10.262 or newer.