# CVE-2020-26143: Security feature bypass in n/a

> Attackers can inject arbitrary data frames into protected Wi-Fi networks by exploiting a flaw in the ALFA Windows 10 driver's handling of fragmented plaintext frames.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 May 2021
- **Updated:** 14 Apr 2026
- **Also known as:** GHSA-c49c-jx24-458g, ROOT-OS-UBUNTU-2204-CVE-2020-26143, UBUNTU-CVE-2020-26143

## What is CVE-2020-26143?

CVE-2020-26143 is a medium-severity vulnerability in n/a, published on 11 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in the ALFA Windows 10 driver 1030.36.604 for AWUS036ACH. The WEP, WPA, WPA2, and WPA3 implementations accept fragmented plaintext frames in a protected Wi-Fi network. An adversary can abuse this to inject arbitrary data frames independent of the network configuration.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2020-26143?

It affects 6 products.


Products: Alfa Awus036h Firmware, Arista C-65 Firmware, Arista C-75 Firmware, Arista O-90 Firmware, Arista W-68 Firmware, Siemens Scalance W700 Ieee 802.11n Firmware.

## How do I fix CVE-2020-26143?

Apply the vendor's patch.

## Is CVE-2020-26143 being exploited?

There is no known exploitation of CVE-2020-26143 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-26140](https://insights.sbomify.com/CVE-2020-26140/): Security feature bypass in n/a (medium 6.5)
- [CVE-2020-26141](https://insights.sbomify.com/CVE-2020-26141/): Security feature bypass in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-26143 and fix it if it is affected.

What it is: CVE-2020-26143 is a medium-severity vulnerability in n/a, published on 11 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-26143 in the wild and no public exploit code.

Affected product: n/a. 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-2020-26143/ (Markdown: https://insights.sbomify.com/CVE-2020-26143/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-26143
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-26143
- OSV: https://osv.dev/vulnerability/CVE-2020-26143

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-26143/
Summaries are generated and may contain mistakes; the official description above is the record.