# CVE-2021-34746: Cisco Enterprise NFV Infrastructure Software Authentication Bypass Vulnerability

> Unauthenticated remote attackers can bypass authentication to log in as administrator on Cisco NFVIS devices due to input validation flaws.

- **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:** 2 Sep 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-hjrv-6xv3-c6x3

## What is CVE-2021-34746?

CVE-2021-34746 is a critical authentication bypass vulnerability in Cisco Enterprise NFV Infrastructure Software, published on 2 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the TACACS+ authentication, authorization and accounting (AAA) feature of Cisco Enterprise NFV Infrastructure Software (NFVIS) could allow an unauthenticated, remote attacker to bypass authentication and log in to an affected device as an administrator. This vulnerability is due to incomplete validation of user-supplied input that is passed to an authentication script. An attacker could exploit this vulnerability by injecting parameters into an authentication request. A successful exploit could allow the attacker to bypass authentication and log in as an administrator to the affected device.

Weakness: CWE-287 (Improper Authentication), CWE-289 (Authentication Bypass by Alternate Name)

## Which versions are affected by CVE-2021-34746?

It affects 1 product.


Products: Cisco Enterprise Nfv Infrastructure Software.

## How do I fix CVE-2021-34746?

No fix has been published for CVE-2021-34746 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34746 being exploited?

There is no known exploitation of CVE-2021-34746 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Enterprise NFV Infrastructure Software

- [CVE-2022-20777](https://insights.sbomify.com/CVE-2022-20777/): Cisco Enterprise NFV Infrastructure Software Vulnerabilities (critical 9.9)
- [CVE-2022-20779](https://insights.sbomify.com/CVE-2022-20779/): Cisco Enterprise NFV Infrastructure Software Vulnerabilities (critical 9.9)
- [CVE-2022-20780](https://insights.sbomify.com/CVE-2022-20780/): Cisco Enterprise NFV Infrastructure Software Vulnerabilities (critical 9.9)
- [CVE-2020-3470](https://insights.sbomify.com/CVE-2020-3470/): Cisco Integrated Management Controller Multiple Remote Code Execution Vulnerabilities (critical 9.8)
- [CVE-2019-1895](https://insights.sbomify.com/CVE-2019-1895/): Cisco Enterprise NFV Infrastructure Software VNC Authentication Bypass Vulnerability (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34746 and fix it if it is affected.

What it is: CVE-2021-34746 is a critical authentication bypass vulnerability in Cisco Enterprise NFV Infrastructure Software, published on 2 Sep 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-2021-34746 in the wild and no public exploit code.

Affected product: Cisco Enterprise NFV Infrastructure Software. 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-2021-34746/ (Markdown: https://insights.sbomify.com/CVE-2021-34746/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34746
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34746
- OSV: https://osv.dev/vulnerability/CVE-2021-34746

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-34746/
Summaries are generated and may contain mistakes; the official description above is the record.