# CVE-2024-7331: TOTOLINK A3300R cstecgi.cgi UploadCustomModule buffer overflow

> Remote attackers can trigger a buffer overflow in the router's CGI script to potentially execute arbitrary code.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Aug 2024
- **Updated:** 1 Aug 2024
- **Also known as:** GHSA-h846-m6mx-wpm3

## What is CVE-2024-7331?

CVE-2024-7331 is a high-severity memory corruption vulnerability in Totolink A3300r Firmware, published on 1 Aug 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was found in TOTOLINK A3300R 17.0.0cu.557_B20221024 and classified as critical. Affected by this issue is the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument File leads to buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. VDB-273254 is the identifier assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2024-7331?

It affects 1 product.


Products: Totolink A3300r Firmware.

## How do I fix CVE-2024-7331?

No fix has been published for CVE-2024-7331 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-7331 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-7331 exists.

## Other vulnerabilities in Totolink A3300r Firmware

- [CVE-2026-31175](https://insights.sbomify.com/CVE-2026-31175/): Command injection in n/a (critical 9.8)
- [CVE-2026-31177](https://insights.sbomify.com/CVE-2026-31177/): Command injection in n/a (critical 9.8)
- [CVE-2026-31178](https://insights.sbomify.com/CVE-2026-31178/): Command injection in n/a (critical 9.8)
- [CVE-2026-31181](https://insights.sbomify.com/CVE-2026-31181/): Command injection in n/a (critical 9.8)
- [CVE-2026-31170](https://insights.sbomify.com/CVE-2026-31170/): Command injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-7331 and fix it if it is affected.

What it is: CVE-2024-7331 is a high-severity memory corruption vulnerability in Totolink A3300r Firmware, published on 1 Aug 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-7331 exists.

Affected product: Totolink A3300r 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-2024-7331/ (Markdown: https://insights.sbomify.com/CVE-2024-7331/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-7331
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-7331
- OSV: https://osv.dev/vulnerability/CVE-2024-7331

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-7331/
Summaries are generated and may contain mistakes; the official description above is the record.