CVE-2026-99263

medium

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: avoid retry wakeup loss when dropping ownership If a wakeup sets IO_POLL_RETRY_FLAG between the owning task consuming the existing instance of IO_POLL_RETRY_FLAG and the loop check of io_poll_check_events(), then we stall on processing the request until an unrelated wakeup comes along. Using atomic_cmpxchg instead of atomic_sub_return to guarantee both the count v and poll_refs are 0 and no wake-ups are missed.

References

https://git.kernel.org/stable/c/eb2a50d8235e4580fea9aa20f3fbe1a002c38cb1

https://git.kernel.org/stable/c/d1f6850086ac6f8b0fa44fb19aa2a468c73ee071

https://git.kernel.org/stable/c/afa407c02f3aa0fd872f86c9bf1b34502e0fa8f0

https://git.kernel.org/stable/c/521e8a65e9b45532295ba1082ef12be6e80c173b

https://git.kernel.org/stable/c/4ef685b8505615729d75c875f52822238bf76ca6

https://git.kernel.org/stable/c/41fae2e9e1fa3bee86aee0a25ba90e59ce5024bf

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-115788

Details

Source: Mitre, NVD

Published: 2026-11-03

Updated: 2026-11-03

Risk Information

CVSS v2

Base Score: 4.9

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

Severity: Medium

CVSS v3

Base Score: 5.5

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

Severity: Medium