CVE-2026-64253

high

Description

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.

References

https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81

https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f

https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd

https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619

Details

Source: Mitre, NVD

Published: 2026-07-24

Updated: 2026-07-24

Risk Information

CVSS v2

Base Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Severity: High