# CVE-2025-15255: Tenda W6-S R7websSsecurityHandler httpd stack-based overflow

> Remote attackers can trigger a stack-based buffer overflow in the Tenda W6-S router's httpd service via the Cookie header, potentially leading to code execution.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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:** 30 Dec 2025
- **Updated:** 24 Feb 2026
- **Also known as:** GHSA-pw2q-c8xj-w9fw

## What is CVE-2025-15255?

CVE-2025-15255 is a critical memory corruption vulnerability in Tenda W6-S, published on 30 Dec 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 Tenda W6-S 1.0.0.4(510). This impacts an unknown function of the file /bin/httpd of the component R7websSsecurityHandler. Executing a manipulation of the argument Cookie can lead to stack-based buffer overflow. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized.

Weakness: CWE-121 (Stack-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2025-15255?

It affects 1 product.


Products: Tenda W6-S Firmware.

## How do I fix CVE-2025-15255?

No fix has been published for CVE-2025-15255 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-15255 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-15255 exists.

## Other vulnerabilities in Tenda W6-S

- [CVE-2022-45497](https://insights.sbomify.com/CVE-2022-45497/): Command injection in n/a (critical 9.8)
- [CVE-2025-28220](https://insights.sbomify.com/CVE-2025-28220/): Memory corruption in n/a (high 7.5)
- [CVE-2025-28221](https://insights.sbomify.com/CVE-2025-28221/): Memory corruption in n/a (high 7.5)
- [CVE-2022-45498](https://insights.sbomify.com/CVE-2022-45498/): Missing authorization in n/a (high 7.5)
- [CVE-2022-45499](https://insights.sbomify.com/CVE-2022-45499/): Memory corruption in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-15255 and fix it if it is affected.

What it is: CVE-2025-15255 is a critical memory corruption vulnerability in Tenda W6-S, published on 30 Dec 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-2025-15255 exists.

Affected product: Tenda W6-S. 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-2025-15255/ (Markdown: https://insights.sbomify.com/CVE-2025-15255/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-15255
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-15255
- OSV: https://osv.dev/vulnerability/CVE-2025-15255

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-15255/
Summaries are generated and may contain mistakes; the official description above is the record.