# CVE-2026-23454: net: mana: fix use-after-free in mana_hwc_destroy_channel() by reordering teardown

> A race condition in the Linux kernel's MANA network driver allows a use-after-free, potentially leading to code execution or system crashes.

- **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Apr 2026
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2026-23454, DEBIAN-CVE-2026-23454, GHSA-v535-7p5c-7xm9, ROOT-OS-DEBIAN-12-CVE-2026-23454, ROOT-OS-DEBIAN-13-CVE-2026-23454, ROOT-OS-UBUNTU-2204-CVE-2026-23454, ROOT-OS-UBUNTU-2404-CVE-2026-23454, UBUNTU-CVE-2026-23454

## What is CVE-2026-23454?

CVE-2026-23454 is a high-severity use after free vulnerability in Linux kernel, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

net: mana: fix use-after-free in mana_hwc_destroy_channel() by reordering teardown

A potential race condition exists in mana_hwc_destroy_channel() where
hwc->caller_ctx is freed before the HWC's Completion Queue (CQ) and
Event Queue (EQ) are destroyed. This allows an in-flight CQ interrupt
handler to dereference freed memory, leading to a use-after-free or
NULL pointer dereference in mana_hwc_handle_resp().

mana_smc_teardown_hwc() signals the hardware to stop but does not
synchronize against IRQ handlers already executing on other CPUs. The
IRQ synchronization only happens in mana_hwc_destroy_cq() via
mana_gd_destroy_eq() -> mana_gd_deregister_irq(). Since this runs
after kfree(hwc->caller_ctx), a concurrent mana_hwc_rx_event_handler()
can dereference freed caller_ctx (and rxq->msg_buf) in
mana_hwc_handle_resp().

Fix this by reordering teardown to reverse-of-creation order: destroy
the TX/RX work queues and CQ/EQ before freeing hwc->caller_ctx. This
ensures all in-flight interrupt handlers complete before the memory they
access is freed.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-23454?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23454?

Apply the vendor's patch.

## Is CVE-2026-23454 being exploited?

There is no known exploitation of CVE-2026-23454 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-23454 and fix it if it is affected.

What it is: CVE-2026-23454 is a high-severity use after free vulnerability in Linux kernel, published on 3 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-23454 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-23454/ (Markdown: https://insights.sbomify.com/CVE-2026-23454/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23454
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23454
- OSV: https://osv.dev/vulnerability/CVE-2026-23454

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23454/
Summaries are generated and may contain mistakes; the official description above is the record.