# CVE-2018-9149: Hardcoded credentials in n/a

> Attackers with physical access can use hardcoded root credentials to gain full system control and enable a Telnet backdoor on the device.

- **Severity:** Medium 6.8 (`CVSS:3.0/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:** 1 Apr 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-9j87-wr37-cwg6

## What is CVE-2018-9149?

CVE-2018-9149 is a medium-severity vulnerability in n/a, published on 1 Apr 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The Zyxel Multy X (AC3000 Tri-Band WiFi System) device doesn't use a suitable mechanism to protect the UART. After an attacker dismantles the device and uses a USB-to-UART cable to connect the device, he can use the 1234 password for the root account to login to the system. Furthermore, an attacker can start the device's TELNET service as a backdoor.

Weakness: CWE-798 (Use of Hard-coded Credentials)

## Which versions are affected by CVE-2018-9149?

It affects 1 product.


Products: Zyxel Ac3000 Firmware.

## How do I fix CVE-2018-9149?

No fix has been published for CVE-2018-9149 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-9149 being exploited?

There is no known exploitation of CVE-2018-9149 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-9149 and fix it if it is affected.

What it is: CVE-2018-9149 is a medium-severity vulnerability in n/a, published on 1 Apr 2018. 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-2018-9149 in the wild and no public exploit code.

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-2018-9149/ (Markdown: https://insights.sbomify.com/CVE-2018-9149/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-9149
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-9149
- OSV: https://osv.dev/vulnerability/CVE-2018-9149

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-9149/
Summaries are generated and may contain mistakes; the official description above is the record.