Vulnerability in Linux

CVE-2026-52933

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (6.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 6.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-52933: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001

Affected products

  • Linux — versions a26a35e9019fd70bf3cf647dcfdae87abc7bacea, 4b702b7d11ce1b9d26fc6d7c5a7ef4ac1d455048, bc4e6ee16778149811333a969a7a893d4cc110c5
  • Linux Kernel — versions 6.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-52933?
CVE-2026-52933 is a high-severity vulnerability in Linux, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 7.8/10. Published 2026-06-24.
How severe is CVE-2026-52933?
High severity. CVSS v3 base score is 7.8 out of 10.