# CVE-2026-7218: Totolink N300RT libapmib.so formWsc is_cmd_string_valid buffer overflow

> Remote attackers can trigger a buffer overflow in the Totolink N300RT router via the formWsc interface, potentially leading to arbitrary code execution.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Apr 2026
- **Updated:** 29 Apr 2026
- **Also known as:** GHSA-76r7-mj3f-42m5

## What is CVE-2026-7218?

CVE-2026-7218 is a high-severity memory corruption vulnerability in Totolink N300RT, published on 28 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

A vulnerability was detected in Totolink N300RT 3.4.0-B20250430. The impacted element is the function is_cmd_string_valid of the file /boafrm/formWsc of the component libapmib.so. Performing a manipulation of the argument localPin results in buffer overflow. The attack is possible to be carried out remotely. The exploit is now public 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-2026-7218?


## How do I fix CVE-2026-7218?

No fix has been published for CVE-2026-7218 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-7218 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-7218 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-7218 and fix it if it is affected.

What it is: CVE-2026-7218 is a high-severity memory corruption vulnerability in Totolink N300RT, published on 28 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-7218 exists.

Affected product: Totolink N300RT. 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-2026-7218/ (Markdown: https://insights.sbomify.com/CVE-2026-7218/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-7218
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-7218
- OSV: https://osv.dev/vulnerability/CVE-2026-7218

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-7218/
Summaries are generated and may contain mistakes; the official description above is the record.