Vulnerability in Linux
CVE-2026-23275
In the Linux kernel, the following vulnerability has been resolved: io_uring: ensure ctx->rings is stable for task work flags manipulation If DEFER_TASKRUN | SETUP_TASKRUN is used and task work is added while the ring is being resized, it's possible for the OR'ing of IORING_SQ_TASKRUN to happen in the small window of swapping into the new rings and the old rings being freed. Prevent this by adding a 2nd ->rings pointer, ->rings_rcu, which is protected by RCU. The task work flags manipulation is inside RCU already, and if the resize ring freeing is done post an RCU synchronize, then there's no need to add locking to the fast path of task work additions. Note: this is only done for DEFER_TASKRUN, as that's the only setup mode that supports ring resizing. If this ever changes, then they too need to use the io_ctx_mark_taskrun() helper.
EPSS: 0.001 (2.3th percentile) — read the EPSS interpretation.
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.
Affected products
- Linux — versions 79cfe9e59c2a12c3b3faeeefe38d23f3d8030972, 6.13, 0
- Linux Linux_kernel — versions 7.0
References
Frequently asked questions
- What is CVE-2026-23275?
- CVE-2026-23275 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-03-20.
- How severe is CVE-2026-23275?
- High severity. CVSS v3 base score is 7.8 out of 10.