Vulnerability Description
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.
CVSS Score
HIGH
References
- https://git.kernel.org/stable/c/46dc07d5f31411cc023f3bf1f4a23a07bf6e0ed1
- https://git.kernel.org/stable/c/7cc4530b3e952d4a5947e1e55d06620d8845d4f5
- https://git.kernel.org/stable/c/96189080265e6bb5dde3a4afbaf947af493e3f82
FAQ
What is CVE-2026-23275?
CVE-2026-23275 is a vulnerability with a CVSS score of 7.8 (HIGH). 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 a...
How severe is CVE-2026-23275?
CVE-2026-23275 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-23275?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.