# CVE-2026-6136: Tenda F451 L7Im frmL7ImForm stack-based overflow

> Remote attackers can trigger a stack-based buffer overflow in the Tenda F451 router via the L7Im form, 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:** 12 Apr 2026
- **Updated:** 14 Apr 2026
- **Also known as:** GHSA-2972-7g9m-9qv2

## What is CVE-2026-6136?

CVE-2026-6136 is a high-severity memory corruption vulnerability in Tenda F451, published on 12 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security vulnerability has been detected in Tenda F451 1.0.0.7_cn_svn7958. Impacted is the function frmL7ImForm of the file /goform/L7Im. The manipulation of the argument page leads to stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed publicly and may be used.

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-2026-6136?

It affects 1 product.


Products: Tenda F451 Firmware.

## How do I fix CVE-2026-6136?

No fix has been published for CVE-2026-6136 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-6136 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-6136 exists.

## Other vulnerabilities in Tenda F451

- [CVE-2026-6120](https://insights.sbomify.com/CVE-2026-6120/): Tenda F451 httpd DhcpListClient fromDhcpListClient stack-based overflow (high 8.7)
- [CVE-2026-6121](https://insights.sbomify.com/CVE-2026-6121/): Tenda F451 httpd WrlclientSet stack-based overflow (high 8.7)
- [CVE-2026-6122](https://insights.sbomify.com/CVE-2026-6122/): Tenda F451 httpd L7Prot frmL7ProtForm stack-based overflow (high 8.7)
- [CVE-2026-6123](https://insights.sbomify.com/CVE-2026-6123/): Tenda F451 httpd addressNat fromAddressNat stack-based overflow (high 8.7)
- [CVE-2026-6124](https://insights.sbomify.com/CVE-2026-6124/): Tenda F451 httpd SafeMacFilter fromSafeMacFilter stack-based overflow (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-6136 and fix it if it is affected.

What it is: CVE-2026-6136 is a high-severity memory corruption vulnerability in Tenda F451, published on 12 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-2026-6136 exists.

Affected product: Tenda F451. 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-2026-6136/ (Markdown: https://insights.sbomify.com/CVE-2026-6136/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-6136
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-6136
- OSV: https://osv.dev/vulnerability/CVE-2026-6136

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-6136/
Summaries are generated and may contain mistakes; the official description above is the record.