# CVE-2026-77022: Comfast CF-N1-S SSID Configuration mbox-config sub_44B438 stack-based overflow

> Remote attackers can trigger a stack-based buffer overflow in the SSID configuration interface to execute arbitrary code on Comfast CF-N1-S routers.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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:** 20 Aug 2026
- **Updated:** 21 Aug 2026
- **Also known as:** GHSA-5pr4-rqrw-x9qc

## What is CVE-2026-77022?

CVE-2026-77022 is a critical memory corruption vulnerability in Comfast CF-N1-S, published on 20 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security flaw has been discovered in Comfast CF-N1-S 2.6.0.1. Affected by this issue is the function sub_44B438 of the file /cgi-bin/mbox-config?method=SET&section=ptest_ssid of the component SSID Configuration. The manipulation of the argument ssid results in stack-based buffer overflow. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.

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-2026-77022?


## How do I fix CVE-2026-77022?

No fix has been published for CVE-2026-77022 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-77022 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-77022 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-77022 and fix it if it is affected.

What it is: CVE-2026-77022 is a critical memory corruption vulnerability in Comfast CF-N1-S, published on 20 Aug 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-2026-77022 exists.

Affected product: Comfast CF-N1-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-2026-77022/ (Markdown: https://insights.sbomify.com/CVE-2026-77022/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-77022
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-77022
- OSV: https://osv.dev/vulnerability/CVE-2026-77022

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-77022/
Summaries are generated and may contain mistakes; the official description above is the record.