CVE-2026-64253: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.1% chance of exploitation in the next 30 days.

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.

Affected products

• Linux Linux Kernel: from 6.9, before 6.12.95 (fixed in 6.12.95); from 6.13, before 6.18.38 (fixed in 6.18.38); from 6.19, before 7.1.3 (fixed in 7.1.3)

Published 2026-07-24. Last modified 2026-08-17.