# CVE-2023-20154: Cisco Modeling Labs External Authentication Bypass Vulnerability

> Unauthenticated remote attackers can bypass authentication to gain administrative access and modify data in Cisco Modeling Labs web interfaces.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:** 15 Nov 2024
- **Updated:** 15 Nov 2024
- **Also known as:** GHSA-g9gm-jgpx-56qm

## What is CVE-2023-20154?

CVE-2023-20154 is a critical authentication bypass vulnerability in Cisco Modeling Labs, published on 15 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the external authentication mechanism of Cisco Modeling Labs could allow an unauthenticated, remote attacker to access the web interface with administrative privileges.

This vulnerability is due to the improper handling of certain messages that are returned by the associated external authentication server. An attacker could exploit this vulnerability by logging in to the web interface of an affected server. Under certain conditions, the authentication mechanism would be bypassed and the attacker would be logged in as an administrator. A successful exploit could allow the attacker to obtain administrative privileges on the web interface of an affected server, including the ability to access and modify every simulation and all user-created data. To exploit this vulnerability, the attacker would need valid user credentials that are stored on the associated external authentication server.
Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.

Weakness: CWE-305 (Authentication Bypass by Primary Weakness)

## Which versions are affected by CVE-2023-20154?

It affects 1 product.


Products: Cisco Modeling Labs.

## How do I fix CVE-2023-20154?

No fix has been published for CVE-2023-20154 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-20154 being exploited?

There is no known exploitation of CVE-2023-20154 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Modeling Labs

- [CVE-2021-1531](https://insights.sbomify.com/CVE-2021-1531/): Cisco Modeling Labs Web UI Command Injection Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-20154 and fix it if it is affected.

What it is: CVE-2023-20154 is a critical authentication bypass vulnerability in Cisco Modeling Labs, published on 15 Nov 2024. 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-2023-20154 in the wild and no public exploit code.

Affected product: Cisco Modeling Labs. 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-2023-20154/ (Markdown: https://insights.sbomify.com/CVE-2023-20154/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20154
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20154
- OSV: https://osv.dev/vulnerability/CVE-2023-20154

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-20154/
Summaries are generated and may contain mistakes; the official description above is the record.