# CVE-2018-0291: Denial of service in Cisco NX-OS unknown

> An authenticated remote attacker can cause a denial of service on Cisco NX-OS devices by sending crafted SNMP packets that trigger unexpected application restarts.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Jun 2018
- **Updated:** 29 Nov 2024
- **Also known as:** GHSA-qwm9-fr49-mf7m

## What is CVE-2018-0291?

CVE-2018-0291 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 20 Jun 2018. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco NX-OS Software could allow an authenticated, remote attacker to cause the SNMP application on an affected device to restart unexpectedly. The vulnerability is due to improper validation of SNMP protocol data units (PDUs) in SNMP packets. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device. A successful exploit could allow the attacker to cause the SNMP application to restart multiple times, leading to a system-level restart and a denial of service (DoS) condition. This vulnerability affects Nexus 2000 Series Switches, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 3600 Platform 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, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCuw99630, CSCvg71290, CSCvj67977.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2018-0291?

It affects 1 product.


Products: Cisco Nx-Os.

## How do I fix CVE-2018-0291?

No fix has been published for CVE-2018-0291 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0291 being exploited?

There is no known exploitation of CVE-2018-0291 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-2018-0291 and fix it if it is affected.

What it is: CVE-2018-0291 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 20 Jun 2018. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-0291 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-2018-0291/ (Markdown: https://insights.sbomify.com/CVE-2018-0291/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0291
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0291
- OSV: https://osv.dev/vulnerability/CVE-2018-0291

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-0291/
Summaries are generated and may contain mistakes; the official description above is the record.