Medium (5.5) in linux linux kernel. EPSS 0.1% chance of exploitation in the next 30 days.
In the Linux kernel, the following vulnerability has been resolved:
io_uring/waitid: clear waitid info before copying it to userspace
IORING_OP_WAITID stores its result fields in struct io_waitid::info and
later copies them to userspace siginfo. The prep path initializes the
request arguments, but it does not initialize info itself.
If the wait operation completes without reporting a child event, the common
wait code can return without writing wo_info. In that case io_waitid_finish()
still copies iw->info to userspace, exposing stale bytes from the reused
io_kiocb command storage.
Clear the result storage during prep so the io_uring path matches the
regular waitid syscall, which uses a zero-initialized struct waitid_info.
Severity
CVSS 3.1
5.5 medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.1% chance of exploitation in the next 30 days; higher than 1% of CVEs (scores of 2026-11-01)