# CVE-2023-35140: Privilege escalation in GS1900-24EP firmware

> An authenticated local user with read-only access can modify system settings on Zyxel GS1900-24EP switches due to improper privilege management.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N`)
- **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:** No
- **Published:** 7 Nov 2023
- **Updated:** 4 Sep 2024
- **Also known as:** GHSA-wcc8-wmx2-r8gp

## What is CVE-2023-35140?

CVE-2023-35140 is a medium-severity vulnerability in Zyxel GS1900-24EP firmware, published on 7 Nov 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The improper privilege management vulnerability in the Zyxel GS1900-24EP switch firmware version V2.70(ABTO.5) could allow an authenticated local user with read-only access to modify system settings on a vulnerable device.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2023-35140?

It affects 10 products.


Products: Zyxel Gs1900-10hp Firmware, Zyxel Gs1900-16 Firmware, Zyxel Gs1900-24 Firmware, Zyxel Gs1900-24e Firmware, Zyxel Gs1900-24ep Firmware, Zyxel Gs1900-24hpv2 Firmware, Zyxel Gs1900-48 Firmware, Zyxel Gs1900-48hpv2 Firmware, Zyxel Gs1900-8 Firmware, Zyxel Gs1900-8hp Firmware.

## How do I fix CVE-2023-35140?

No fix has been published for CVE-2023-35140 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-35140 being exploited?

There is no known exploitation of CVE-2023-35140 in the wild and no public exploit code.

## Other vulnerabilities in Zyxel GS1900-24EP firmware

- [CVE-2026-7273](https://insights.sbomify.com/CVE-2026-7273/): Zyxel GS1900 Series Switches Stack-Based Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2019-15800](https://insights.sbomify.com/CVE-2019-15800/): Command injection in n/a (critical 9.8)
- [CVE-2015-5988](https://insights.sbomify.com/CVE-2015-5988/): Hardcoded credentials in n/a (critical 9.8)
- [CVE-2015-5989](https://insights.sbomify.com/CVE-2015-5989/): Auth bypass in n/a (critical 9.8)
- [CVE-2019-15803](https://insights.sbomify.com/CVE-2019-15803/): Auth bypass in n/a (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-35140 and fix it if it is affected.

What it is: CVE-2023-35140 is a medium-severity vulnerability in Zyxel GS1900-24EP firmware, published on 7 Nov 2023. 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-2023-35140 in the wild and no public exploit code.

Affected product: Zyxel GS1900-24EP firmware. 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-2023-35140/ (Markdown: https://insights.sbomify.com/CVE-2023-35140/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-35140
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-35140
- OSV: https://osv.dev/vulnerability/CVE-2023-35140

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-35140/
Summaries are generated and may contain mistakes; the official description above is the record.