# CVE-2019-1968: Cisco NX-OS Software NX-API Denial of Service Vulnerability

> An unauthenticated remote attacker can cause a denial of service in the NX-API service by sending a crafted HTTP request, requiring the feature to be enabled.

- **Severity:** Medium 5.3 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Aug 2019
- **Updated:** 19 Nov 2024
- **Also known as:** GHSA-cp28-47gg-22cx

## What is CVE-2019-1968?

CVE-2019-1968 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 29 Aug 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an NX-API system process to unexpectedly restart. The vulnerability is due to incorrect validation of the HTTP header of a request that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP request to the NX-API on an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition in the NX-API service; however, the NX-OS device itself would still be available and passing network traffic. Note: The NX-API feature is disabled by default.

Weakness: CWE-116 (Improper Encoding or Escaping of Output), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2019-1968?

It affects 1 product.


Products: Cisco Nx-Os.

## How do I fix CVE-2019-1968?

No fix has been published for CVE-2019-1968 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-1968 being exploited?

There is no known exploitation of CVE-2019-1968 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-2019-1968 and fix it if it is affected.

What it is: CVE-2019-1968 is a medium-severity denial of service vulnerability in Cisco Nx-Os, published on 29 Aug 2019. 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-2019-1968 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-2019-1968/ (Markdown: https://insights.sbomify.com/CVE-2019-1968/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1968
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1968
- OSV: https://osv.dev/vulnerability/CVE-2019-1968

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-1968/
Summaries are generated and may contain mistakes; the official description above is the record.