# CVE-2024-4247: Tenda i21 formQosManage_auto stack-based overflow

> Remote attackers can trigger a stack-based buffer overflow in the Tenda i21 router via the ssidIndex argument, potentially leading to code execution or denial of service.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 27 Apr 2024
- **Updated:** 1 Aug 2024
- **Also known as:** GHSA-m5cm-ff2v-j4hc

## What is CVE-2024-4247?

CVE-2024-4247 is a high-severity memory corruption vulnerability in Tenda i21, published on 27 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability has been found in Tenda i21 1.0.0.14(4656) and classified as critical. This vulnerability affects the function formQosManage_auto. The manipulation of the argument ssidIndex leads to stack-based buffer overflow. The attack can be initiated remotely. VDB-262138 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-787 (Out-of-bounds Write), CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2024-4247?

It affects 1 product.


Products: Tenda I21 Firmware.

## How do I fix CVE-2024-4247?

No fix has been published for CVE-2024-4247 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-4247 being exploited?

There is no known exploitation of CVE-2024-4247 in the wild and no public exploit code.

## Other vulnerabilities in Tenda i21

- [CVE-2022-44362](https://insights.sbomify.com/CVE-2022-44362/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-44363](https://insights.sbomify.com/CVE-2022-44363/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-44365](https://insights.sbomify.com/CVE-2022-44365/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-44366](https://insights.sbomify.com/CVE-2022-44366/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-44367](https://insights.sbomify.com/CVE-2022-44367/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-4247 and fix it if it is affected.

What it is: CVE-2024-4247 is a high-severity memory corruption vulnerability in Tenda i21, published on 27 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-4247 in the wild and no public exploit code.

Affected product: Tenda i21. 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-2024-4247/ (Markdown: https://insights.sbomify.com/CVE-2024-4247/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-4247
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-4247
- OSV: https://osv.dev/vulnerability/CVE-2024-4247

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-4247/
Summaries are generated and may contain mistakes; the official description above is the record.