What is CVE-2026-43121?

CVE-2026-43121 is a medium-severity vulnerability in Linux, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 4.7/10. Published 2026-05-06.

How severe is CVE-2026-43121?

Medium severity. CVSS v3 base score is 4.7 out of 10.

Vulnerability in Linux

CVE-2026-43121

In the Linux kernel, the following vulnerability has been resolved: io_uring/zcrx: fix user_ref race between scrub and refill paths The io_zcrx_put_niov_uref() function uses a non-atomic check-then-decrement pattern (atomic_read followed…

Vulnerability class: Race Condition

EPSS: 0.000 (1.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Linux — versions 34a3e60821ab9f335a58d43a88cccdbefdebdec3, 6.15, 0
Linux Linux_kernel

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2026-43121?: CVE-2026-43121 is a medium-severity vulnerability in Linux, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 4.7/10. Published 2026-05-06.
How severe is CVE-2026-43121?: Medium severity. CVSS v3 base score is 4.7 out of 10.