# CVE-2021-32951: Advantech WebAccess/NMS Improper Authentication

> Unauthorized users can bypass authentication to view monitored resources and device details in Advantech WebAccess/NMS.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Oct 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-9rgm-96q6-gc9m

## What is CVE-2021-32951?

CVE-2021-32951 is a medium-severity authentication bypass vulnerability in Advantech WebAccess/NMS, published on 27 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

WebAccess/NMS (Versions prior to v3.0.3_Build6299) has an improper authentication vulnerability, which may allow unauthorized users to view resources monitored and controlled by the WebAccess/NMS, as well as IP addresses and names of all the devices managed via WebAccess/NMS.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2021-32951?

It affects 1 product.


Products: Advantech Webaccess\/Nms.

## How do I fix CVE-2021-32951?

No fix has been published for CVE-2021-32951 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-32951 being exploited?

There is no known exploitation of CVE-2021-32951 in the wild and no public exploit code.

## Other vulnerabilities in Advantech WebAccess/NMS

- [CVE-2020-10621](https://insights.sbomify.com/CVE-2020-10621/): File upload in WebAccess/NMS (critical 9.8)
- [CVE-2020-10625](https://insights.sbomify.com/CVE-2020-10625/): Auth bypass in WebAccess/NMS (critical 9.8)
- [CVE-2020-10631](https://insights.sbomify.com/CVE-2020-10631/): Path traversal in WebAccess/NMS (critical 9.8)
- [CVE-2020-10619](https://insights.sbomify.com/CVE-2020-10619/): Path traversal in WebAccess/NMS (critical 9.1)
- [CVE-2020-10603](https://insights.sbomify.com/CVE-2020-10603/): Command injection in WebAccess/NMS (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-32951 and fix it if it is affected.

What it is: CVE-2021-32951 is a medium-severity authentication bypass vulnerability in Advantech WebAccess/NMS, published on 27 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-32951 in the wild and no public exploit code.

Affected product: Advantech WebAccess/NMS. 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-2021-32951/ (Markdown: https://insights.sbomify.com/CVE-2021-32951/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-32951
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-32951
- OSV: https://osv.dev/vulnerability/CVE-2021-32951

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-32951/
Summaries are generated and may contain mistakes; the official description above is the record.