In the Linux kernel, the following vulnerability has been resolved: kernel/fork: clear PF_BLOCK_TS in copy_process() PF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is non-NULL, and blk_finish_plug() clears it via __blk_flush_plug() before NULLing the plug pointer. copy_process() breaks the invariant by inheriting PF_BLOCK_TS from the parent while resetting the child's plug to NULL. Clear PF_BLOCK_TS alongside that assignment so callers can rely on "PF_BLOCK_TS set implies current->plug != NULL" and dereference current->plug unguarded.

A flaw was found in the Linux kernel. The `copy_process()` function, responsible for creating new processes, incorrectly inherits a flag (`PF_BLOCK_TS`) from the parent process while simultaneously setting a related pointer (`current->plug`) to null in the child process. This inconsistency can lead to the kernel attempting to access a null pointer without proper validation. A local attacker could potentially exploit this to trigger a system crash, leading to a Denial of Service (DoS).

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Out of support scope kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-64253 https://nvd.nist.gov/vuln/detail/CVE-2026-64253 https://lore.kernel.org/linux-cve-announce/2026072420-CVE-2026-64253-5b3f@gregkh/T