# CVE-2025-6401: TOTOLINK N300RH HTTP POST Message formFilter denial of service

> An attacker can cause a denial of service on TOTOLINK N300RH routers by manipulating the url argument in the HTTP POST Message Handler.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **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:** 21 Jun 2025
- **Updated:** 23 Jun 2025
- **Also known as:** GHSA-vvr6-g6xc-j272

## What is CVE-2025-6401?

CVE-2025-6401 is a medium-severity denial of service vulnerability in TOTOLINK N300RH, published on 21 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was found in TOTOLINK N300RH 6.1c.1390_B20191101. It has been classified as problematic. This affects an unknown part of the file /boafrm/formFilter of the component HTTP POST Message Handler. The manipulation of the argument url leads to denial of service. The exploit has been disclosed to the public and may be used.

Weakness: CWE-404 (Improper Resource Shutdown or Release)

## Which versions are affected by CVE-2025-6401?

It affects 1 product.


Products: Totolink N300rh Firmware.

## How do I fix CVE-2025-6401?

No fix has been published for CVE-2025-6401 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-6401 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-6401 exists.

## Other vulnerabilities in TOTOLINK N300RH

- [CVE-2026-3301](https://insights.sbomify.com/CVE-2026-3301/): Totolink N300RH Web Management cstecgi.cgi setWebWlanIdx os command injection (critical 9.3)
- [CVE-2025-6400](https://insights.sbomify.com/CVE-2025-6400/): TOTOLINK N300RH HTTP POST Message formPortFw buffer overflow (high 8.7)
- [CVE-2026-3696](https://insights.sbomify.com/CVE-2026-3696/): Totolink N300RH CGI cstecgi.cgi setWiFiWpsConfig os command injection (medium 6.9)
- [CVE-2025-4849](https://insights.sbomify.com/CVE-2025-4849/): TOTOLINK N300RH cstecgi.cgi CloudACMunualUpdateUserdata command injection (medium 5.3)
- [CVE-2025-4850](https://insights.sbomify.com/CVE-2025-4850/): TOTOLINK N300RH cstecgi.cgi setUnloadUserData command injection (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-6401 and fix it if it is affected.

What it is: CVE-2025-6401 is a medium-severity denial of service vulnerability in TOTOLINK N300RH, published on 21 Jun 2025. 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-2025-6401 exists.

Affected product: TOTOLINK N300RH. 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-2025-6401/ (Markdown: https://insights.sbomify.com/CVE-2025-6401/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-6401
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-6401
- OSV: https://osv.dev/vulnerability/CVE-2025-6401

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-6401/
Summaries are generated and may contain mistakes; the official description above is the record.