# CVE-2025-9935: TOTOLINK N600R cstecgi.cgi sub_4159F8 command injection

> Remote attackers can execute arbitrary commands on TOTOLINK N600R routers via a command injection vulnerability in the web interface.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 Sep 2025
- **Updated:** 4 Sep 2025
- **Also known as:** GHSA-9f5w-jc5j-mr6j

## What is CVE-2025-9935?

CVE-2025-9935 is a medium-severity command injection vulnerability in TOTOLINK N600R, published on 3 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was determined in TOTOLINK N600R 4.3.0cu.7866_B20220506. This vulnerability affects the function sub_4159F8 of the file /web_cste/cgi-bin/cstecgi.cgi. Executing manipulation can lead to command injection. The attack can be executed remotely. The exploit has been publicly disclosed and may be utilized.

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2025-9935?

It affects 1 product.


Products: Totolink N600r Firmware.

## How do I fix CVE-2025-9935?

No fix has been published for CVE-2025-9935 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-9935 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-9935 exists.

## Other vulnerabilities in TOTOLINK N600R

- [CVE-2025-51390](https://insights.sbomify.com/CVE-2025-51390/): Command injection in n/a (critical 9.8)
- [CVE-2025-46060](https://insights.sbomify.com/CVE-2025-46060/): Memory corruption in n/a (critical 9.8)
- [CVE-2025-22900](https://insights.sbomify.com/CVE-2025-22900/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-28905](https://insights.sbomify.com/CVE-2022-28905/): Command injection in n/a (critical 9.8)
- [CVE-2022-28906](https://insights.sbomify.com/CVE-2022-28906/): Command injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-9935 and fix it if it is affected.

What it is: CVE-2025-9935 is a medium-severity command injection vulnerability in TOTOLINK N600R, published on 3 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-9935 exists.

Affected product: TOTOLINK N600R. 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-2025-9935/ (Markdown: https://insights.sbomify.com/CVE-2025-9935/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-9935
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-9935
- OSV: https://osv.dev/vulnerability/CVE-2025-9935

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-9935/
Summaries are generated and may contain mistakes; the official description above is the record.