# CVE-2026-36738: Missing authorization in n/a

> An attacker with physical access can connect to the UART interface to gain unrestricted control over the router due to missing authentication.

- **Severity:** Medium 6.8 (`CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 May 2026
- **Updated:** 14 May 2026
- **Also known as:** GHSA-hxf8-x6wv-3579

## What is CVE-2026-36738?

CVE-2026-36738 is a medium-severity missing authorization vulnerability in n/a, published on 13 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

U-SPEED AC1200 Gigabit Wi-Fi Router (Model: T18-21K) V1.0 is vulnerable to Incorrect Access Control. The device exposes a UART interface that lacks authentication, authorization, or access control mechanisms. An attacker with physical access to the UART pins can connect to the interface and gain unrestricted access to device functionality.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2026-36738?

It affects 1 product.


Products: U-Speed T18-21k Firmware.

## How do I fix CVE-2026-36738?

No fix has been published for CVE-2026-36738 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-36738 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-36738 exists.

## Other vulnerabilities in n/a

- [CVE-2026-36741](https://insights.sbomify.com/CVE-2026-36741/): Command injection in n/a (high 7.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-36738 and fix it if it is affected.

What it is: CVE-2026-36738 is a medium-severity missing authorization vulnerability in n/a, published on 13 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-36738 exists.

Affected product: n/a. 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-2026-36738/ (Markdown: https://insights.sbomify.com/CVE-2026-36738/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-36738
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-36738
- OSV: https://osv.dev/vulnerability/CVE-2026-36738

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-36738/
Summaries are generated and may contain mistakes; the official description above is the record.