# CVE-2021-40859: Auth bypass in n/a

> Backdoors in Auerswald COMpact devices allow attackers with web management access to gain full administrative control.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Dec 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-69pv-7jmq-p3xp

## What is CVE-2021-40859?

CVE-2021-40859 is a critical authentication bypass vulnerability in n/a, published on 7 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Backdoors were discovered in Auerswald COMpact 5500R 7.8A and 8.0B devices, that allow attackers with access to the web based management application full administrative access to the device.

## Which versions are affected by CVE-2021-40859?

It affects 1 product.


Products: Auerswald Compact 5500r Firmware.

## How do I fix CVE-2021-40859?

No fix has been published for CVE-2021-40859 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40859 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-40859 exists.

Public exploit code:

- Auerswald COMpact 8.0B Backdoors exploit (github_poc): https://github.com/419066074/CVE-2021-40859
- Auerswald VoIP System Secret Backdoors -PoC (github_poc): https://github.com/pussycat0x/CVE-2021-40859
- Auerswald COMpact 8.0B - Multiple Backdoors (exploitdb)
- Auerswald COMpact 5500R 7.8A and 8.0B Devices Backdoor (nuclei): http/cves/2021/CVE-2021-40859.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40859 and fix it if it is affected.

What it is: CVE-2021-40859 is a critical authentication bypass vulnerability in n/a, published on 7 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-40859 exists.

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-2021-40859/ (Markdown: https://insights.sbomify.com/CVE-2021-40859/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40859
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40859
- OSV: https://osv.dev/vulnerability/CVE-2021-40859

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40859/
Summaries are generated and may contain mistakes; the official description above is the record.