# CVE-2025-11847: Null dereference in VMG3625-T50B firmware

> An authenticated administrator can cause a denial-of-service condition in Zyxel routers by sending a crafted HTTP request to the IP settings CGI program.

- **Severity:** Medium 4.9 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Feb 2026
- **Updated:** 24 Feb 2026
- **Also known as:** GHSA-qhmq-843h-9vq8

## What is CVE-2025-11847?

CVE-2025-11847 is a medium-severity vulnerability in Zyxel VMG3625-T50B firmware, published on 24 Feb 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

A null pointer dereference vulnerability in the IP settings CGI program of the Zyxel VMG3625-T50B firmware versions through 5.50(ABPM.9.6)C0 and the Zyxel WX3100-T0 firmware versions through 5.50(ABVL.4.8)C0 could allow an authenticated attacker with administrator privileges to trigger a denial-of-service (DoS) condition by sending a crafted HTTP request.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-11847?

It affects 54 products.


Products: Zyxel Ax7501-B1 Firmware, Zyxel Dx3300-T0 Firmware, Zyxel Dx3300-T1 Firmware, Zyxel Dx3301-T0 Firmware, Zyxel Dx4510-B0 Firmware, Zyxel Dx4510-B1 Firmware, Zyxel Dx5401-B1 Firmware, Zyxel Ee3301-00 Firmware, Zyxel Ee5301-00 Firmware, Zyxel Ee6510-10 Firmware, Zyxel Emg3525-T50b Firmware, Zyxel Emg5523-T50b Firmware, Zyxel Ex2210-T0 Firmware, Zyxel Ex3300-T0 Firmware, Zyxel Ex3300-T1 Firmware, Zyxel Ex3301-T0 Firmware, Zyxel Ex3500-T0 Firmware, Zyxel Ex3501-T0 Firmware, Zyxel Ex3510-B0 Firmware, Zyxel Ex3510-B1 Firmware and 34 more.

## How do I fix CVE-2025-11847?

No fix has been published for CVE-2025-11847 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-11847 being exploited?

There is no known exploitation of CVE-2025-11847 in the wild and no public exploit code.

## Other vulnerabilities in Zyxel VMG3625-T50B firmware

- [CVE-2025-11845](https://insights.sbomify.com/CVE-2025-11845/): Null dereference in VMG3625-T50B firmware (medium 4.9)
- [CVE-2025-11846](https://insights.sbomify.com/CVE-2025-11846/): Null dereference in VMG3625-T50B firmware (medium 4.9)
- [CVE-2025-11848](https://insights.sbomify.com/CVE-2025-11848/): Null dereference in VMG3625-T50B firmware (medium 4.9)
- [CVE-2024-38267](https://insights.sbomify.com/CVE-2024-38267/): Memory corruption in VMG8825-T50K firmware (medium 4.9)
- [CVE-2024-38268](https://insights.sbomify.com/CVE-2024-38268/): Memory corruption in VMG8825-T50K firmware (medium 4.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-11847 and fix it if it is affected.

What it is: CVE-2025-11847 is a medium-severity vulnerability in Zyxel VMG3625-T50B firmware, published on 24 Feb 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-11847 in the wild and no public exploit code.

Affected product: Zyxel VMG3625-T50B 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-2025-11847/ (Markdown: https://insights.sbomify.com/CVE-2025-11847/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-11847
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-11847
- OSV: https://osv.dev/vulnerability/CVE-2025-11847

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-11847/
Summaries are generated and may contain mistakes; the official description above is the record.