# CVE-2026-27512: Tenda F3 Reflected Script Execution via Missing nosniff Header

> Attackers can execute scripts in the admin interface via MIME sniffing due to missing nosniff headers, potentially compromising router administration.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 23 Feb 2026
- **Updated:** 25 May 2026
- **Also known as:** GHSA-62pw-p3ph-rgh9

## What is CVE-2026-27512?

CVE-2026-27512 is a medium-severity cross-site scripting vulnerability in Shenzhen Tenda Technology Co., Ltd. Tenda F3, published on 23 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Shenzhen Tenda F3 Wireless Router firmware V12.01.01.55_multi contains a content-type confusion vulnerability in the administrative interface. Responses omit the X-Content-Type-Options: nosniff header and include attacker-influenced content that can be reflected into the response body. Under affected browser behaviors, MIME sniffing may cause the response to be interpreted as active HTML, enabling script execution in the context of the administrative interface.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-27512?

It affects 1 product.


Products: Tenda F3 Firmware.

## How do I fix CVE-2026-27512?

No fix has been published for CVE-2026-27512 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-27512 being exploited?

There is no known exploitation of CVE-2026-27512 in the wild and no public exploit code.

## Other vulnerabilities in Shenzhen Tenda Technology Co., Ltd. Tenda F3

- [CVE-2020-35391](https://insights.sbomify.com/CVE-2020-35391/): Information disclosure in n/a (critical 9.6)
- [CVE-2026-27514](https://insights.sbomify.com/CVE-2026-27514/): Tenda F3 Plaintext Credential Exposure in Configuration Download (high 7.1)
- [CVE-2025-57569](https://insights.sbomify.com/CVE-2025-57569/): Memory corruption in n/a (medium 5.6)
- [CVE-2025-57570](https://insights.sbomify.com/CVE-2025-57570/): Memory corruption in n/a (medium 5.6)
- [CVE-2025-57571](https://insights.sbomify.com/CVE-2025-57571/): Memory corruption in n/a (medium 5.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-27512 and fix it if it is affected.

What it is: CVE-2026-27512 is a medium-severity cross-site scripting vulnerability in Shenzhen Tenda Technology Co., Ltd. Tenda F3, published on 23 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-27512 in the wild and no public exploit code.

Affected product: Shenzhen Tenda Technology Co., Ltd. Tenda F3. 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-2026-27512/ (Markdown: https://insights.sbomify.com/CVE-2026-27512/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27512
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27512
- OSV: https://osv.dev/vulnerability/CVE-2026-27512

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-27512/
Summaries are generated and may contain mistakes; the official description above is the record.