# CVE-2025-71021: Memory corruption in n/a

> Attackers can cause a Denial of Service on Tenda AX-1806 routers via a crafted request triggering a stack overflow.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Jan 2026
- **Updated:** 14 Jan 2026
- **Also known as:** GHSA-29x9-q4j7-wg69

## What is CVE-2025-71021?

CVE-2025-71021 is a high-severity memory corruption vulnerability in Tenda Ax1806 Firmware, published on 14 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Tenda AX-1806 v1.0.0.1 was discovered to contain a stack overflow in the serverName parameter of the sub_65A28 function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted request.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2025-71021?

It affects 1 product.


Products: Tenda Ax1806 Firmware.

## How do I fix CVE-2025-71021?

No fix has been published for CVE-2025-71021 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-71021 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-71021 exists.

## Other vulnerabilities in Tenda Ax1806 Firmware

- [CVE-2024-44551](https://insights.sbomify.com/CVE-2024-44551/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-44555](https://insights.sbomify.com/CVE-2024-44555/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-40415](https://insights.sbomify.com/CVE-2024-40415/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-35571](https://insights.sbomify.com/CVE-2024-35571/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-35580](https://insights.sbomify.com/CVE-2024-35580/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-71021 and fix it if it is affected.

What it is: CVE-2025-71021 is a high-severity memory corruption vulnerability in Tenda Ax1806 Firmware, published on 14 Jan 2026. 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-2025-71021 exists.

Affected product: Tenda Ax1806 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-2025-71021/ (Markdown: https://insights.sbomify.com/CVE-2025-71021/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-71021
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-71021
- OSV: https://osv.dev/vulnerability/CVE-2025-71021

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-71021/
Summaries are generated and may contain mistakes; the official description above is the record.