# CVE-2026-5567: Tenda M3 Destination setAdvPolicyData buffer overflow

> Remote attackers can trigger a buffer overflow in the Tenda M3 router via the setAdvPolicyData function, potentially leading to code execution or service disruption.

- **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/E:P`)
- **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:** 5 Apr 2026
- **Updated:** 6 Apr 2026
- **Also known as:** GHSA-jwvm-hq84-h9cj

## What is CVE-2026-5567?

CVE-2026-5567 is a high-severity memory corruption vulnerability in Tenda M3, published on 5 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A flaw has been found in Tenda M3 1.0.0.10. This vulnerability affects the function setAdvPolicyData of the file /goform/setAdvPolicyData of the component Destination Handler. Executing a manipulation of the argument policyType can lead to buffer overflow. The attack can be executed remotely. The exploit has been published and may be used.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-5567?

It affects 1 product.


Products: Tenda M3 Firmware.

## How do I fix CVE-2026-5567?

No fix has been published for CVE-2026-5567 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5567 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-5567 exists.

## Other vulnerabilities in Tenda M3

- [CVE-2023-51090](https://insights.sbomify.com/CVE-2023-51090/): Memory corruption in n/a (critical 9.8)
- [CVE-2023-51091](https://insights.sbomify.com/CVE-2023-51091/): Memory corruption in n/a (critical 9.8)
- [CVE-2023-51093](https://insights.sbomify.com/CVE-2023-51093/): Memory corruption in n/a (critical 9.8)
- [CVE-2023-51094](https://insights.sbomify.com/CVE-2023-51094/): Command injection in n/a (critical 9.8)
- [CVE-2023-51095](https://insights.sbomify.com/CVE-2023-51095/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5567 and fix it if it is affected.

What it is: CVE-2026-5567 is a high-severity memory corruption vulnerability in Tenda M3, published on 5 Apr 2026. 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-2026-5567 exists.

Affected product: Tenda M3. 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-2026-5567/ (Markdown: https://insights.sbomify.com/CVE-2026-5567/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5567
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5567
- OSV: https://osv.dev/vulnerability/CVE-2026-5567

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5567/
Summaries are generated and may contain mistakes; the official description above is the record.