CVE-2026-52933EPSS p2.2%
CVE-2026-52933CVE-2026-52933
linux / linux_kernel
Description
In the Linux kernel, the following vulnerability has been resolved:
io_uring/poll: fix signed comparison in io_poll_get_ownership()
io_poll_get_ownership() uses a signed comparison to check whether
poll_refs has reached the threshold for the slowpath:
if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))
atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG
(BIT(31)) is set in poll_refs, the value becomes negative in
signed arithmetic, so the >= 128 comparison always evaluates to
false and the slowpath is never taken.
Fix this by casting the atomic_read() result to unsigned int
before the comparison, so that the cancel flag is treated as a
large positive value and correctly triggers the slowpath.
Scoring
| CVSS | 7.8 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 0.12% probability of exploitation · percentile 2.2% · 2026-08-10T12:02:48Z |
| Last modified | 2026-07-08 |