# CVE-2017-12336: Command injection in Cisco NX-OS

> Authenticated local attackers can escape the TCL shell sandbox to execute arbitrary commands on the underlying operating system of Cisco NX-OS devices.

- **Severity:** Medium 4.2 (`CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Nov 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-v5g5-j6gp-xj36

## What is CVE-2017-12336?

CVE-2017-12336 is a medium-severity command injection vulnerability in Cisco Nx-Os, published on 30 Nov 2017. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the TCL scripting subsystem of Cisco NX-OS System Software could allow an authenticated, local attacker to escape the interactive TCL shell and gain unauthorized access to the underlying operating system of the device. The vulnerability exists due to insufficient input validation of user-supplied files passed to the interactive TCL shell of the affected device. An attacker could exploit this vulnerability to escape the scripting sandbox and execute arbitrary commands on the underlying operating system with the privileges of the authenticated user. To exploit this vulnerability, an attacker must have local access and be authenticated to the targeted device with administrative or tclsh execution privileges. This vulnerability affects the following products running Cisco NX-OS System Software: Multilayer Director Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5000 Series Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, Unified Computing System Manager. Cisco Bug IDs: CSCve93750, CSCve93762, CSCve93763, CSCvg04127.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2017-12336?

It affects 2 products.


Products: Cisco Nx-Os, Cisco Unified Computing System.

## How do I fix CVE-2017-12336?

No fix has been published for CVE-2017-12336 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-12336 being exploited?

There is no known exploitation of CVE-2017-12336 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Nx-Os

- [CVE-2024-20399](https://insights.sbomify.com/CVE-2024-20399/): Cisco NX-OS Command Injection (medium 6.0, exploited in the wild)
- [CVE-2021-1361](https://insights.sbomify.com/CVE-2021-1361/): Cisco NX-OS Software Unauthenticated Arbitrary File Actions Vulnerability (critical 9.8)
- [CVE-2018-0301](https://insights.sbomify.com/CVE-2018-0301/): Memory corruption in Cisco NX-OS unknown (critical 9.8)
- [CVE-2016-1453](https://insights.sbomify.com/CVE-2016-1453/): Memory corruption in n/a (critical 9.8)
- [CVE-2016-1341](https://insights.sbomify.com/CVE-2016-1341/): Hardcoded credentials in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-12336 and fix it if it is affected.

What it is: CVE-2017-12336 is a medium-severity command injection vulnerability in Cisco Nx-Os, published on 30 Nov 2017. 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-2017-12336 in the wild and no public exploit code.

Affected product: Cisco Nx-Os. 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-2017-12336/ (Markdown: https://insights.sbomify.com/CVE-2017-12336/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-12336
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-12336
- OSV: https://osv.dev/vulnerability/CVE-2017-12336

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-12336/
Summaries are generated and may contain mistakes; the official description above is the record.