# CVE-2026-90433: spi: oc-tiny: switch to managed controller allocation

> A use-after-free vulnerability in the Linux kernel's oc-tiny SPI driver allows attackers to cause a denial of service or potentially execute code via late interrupts.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-102828, BELL-CVE-2026-90433, DEBIAN-CVE-2026-90433, GHSA-mj54-2c5f-648c, UBUNTU-CVE-2026-90433

## What is CVE-2026-90433?

CVE-2026-90433 is an use after free vulnerability in Linux, published on 17 Sep 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:

spi: oc-tiny: switch to managed controller allocation

The controller is allocated with the non-managed spi_alloc_host() while
the interrupt is registered with devm_request_irq().  During removal,
spi_bitbang_stop() only unregisters the controller; the subsequent
spi_controller_put() then frees the controller together with its
embedded driver-private devdata, which is the IRQ handler's dev_id.  The
devm_request_irq() release action (free_irq()), which drains the
handler, does not run until after .remove() returns.  A late or latched
interrupt can therefore reach tiny_spi_irq() and dereference
already-freed memory (e.g. hw->base).

Switch to devm_spi_alloc_host() so that the devres LIFO order releases
the controller only after free_irq() has drained the handler, and drop
the now-redundant spi_controller_put() from .remove().  The probe error
path is simplified to direct returns.

This issue was found by an in-house static analysis tool.

## Which versions are affected by CVE-2026-90433?


## How do I fix CVE-2026-90433?

Apply the vendor's patch.

## Is CVE-2026-90433 being exploited?

There is no known exploitation of CVE-2026-90433 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90433 and fix it if it is affected.

What it is: CVE-2026-90433 is an use after free vulnerability in Linux, published on 17 Sep 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-2026-90433 in the wild and no public exploit code.

Affected product: Linux. 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-2026-90433/ (Markdown: https://insights.sbomify.com/CVE-2026-90433/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90433
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90433
- OSV: https://osv.dev/vulnerability/CVE-2026-90433

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90433/
Summaries are generated and may contain mistakes; the official description above is the record.