Vulnerability Details CVE-2026-46259
In the Linux kernel, the following vulnerability has been resolved:
procfs: fix missing RCU protection when reading real_parent in do_task_stat()
When reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent
without proper RCU protection, which leads to:
cpu 0 cpu 1
----- -----
do_task_stat
var = task->real_parent
release_task
call_rcu(delayed_put_task_struct)
task_tgid_nr_ns(var)
rcu_read_lock <--- Too late to protect task->real_parent!
task_pid_ptr <--- UAF!
rcu_read_unlock
This patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add
proper RCU protection for accessing task->real_parent.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 2.4%
CVSS Severity
CVSS v3 Score 7.8
References
- https://git.kernel.org/stable/c/0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e
- https://git.kernel.org/stable/c/1c8dc5b5517546c68ffae40b948336122bb61306
- https://git.kernel.org/stable/c/4f9ae386861e280b7631ca252f798d25575627ee
- https://git.kernel.org/stable/c/73ec7c96601d61d52310c659145bb06d933a0fa6
- https://git.kernel.org/stable/c/76149d53502cf17ef3ae454ff384551236fba867
- https://git.kernel.org/stable/c/c93a33f28f915d446eea6fb3f0e1def0b3af1982
- https://git.kernel.org/stable/c/dd8b13cb4ff1a4545a214ed897fdf2bc341155b6
- https://git.kernel.org/stable/c/fefa0fcd78be465b7ad4c497fa6ec90d64194c04