# CVE-2026-90337: serial: core: do fallible allocations before the console can be registered

> A use-after-free vulnerability in the Linux kernel serial core allows local attackers to cause a denial of service or potentially execute code via failed port bindings.

- **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-102414, BELL-CVE-2026-90337, DEBIAN-CVE-2026-90337, GHSA-3m6c-788w-h698, UBUNTU-CVE-2026-90337

## What is CVE-2026-90337?

CVE-2026-90337 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:

serial: core: do fallible allocations before the console can be registered

serial_core_add_one_port() allocates uport->tty_groups after
uart_configure_port(), which may register the console. If the allocation
fails, the driver unwinds the port while its console remains registered.
The earlier uport->name allocation has a related failure path that leaves
state->uart_port linked to a port being freed.

Failslab reproduced a NULL dereference in PL011 console output and a KASAN
use-after-free in i.MX console output after failed binds.

Allocate the name and tty_groups before linking the port and configuring
it. Reserve space for the optional driver attribute group because
config_port() may populate uport->attr_group during configuration.

## Which versions are affected by CVE-2026-90337?


## How do I fix CVE-2026-90337?

Apply the vendor's patch.

## Is CVE-2026-90337 being exploited?

There is no known exploitation of CVE-2026-90337 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90337 and fix it if it is affected.

What it is: CVE-2026-90337 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-2026-90337 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-2026-90337/ (Markdown: https://insights.sbomify.com/CVE-2026-90337/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90337
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90337
- OSV: https://osv.dev/vulnerability/CVE-2026-90337

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90337/
Summaries are generated and may contain mistakes; the official description above is the record.