# CVE-2019-16026: Cisco Mobility Management Entity Denial of Service Vulnerability

> An unauthenticated remote attacker can cause a denial of service on connected eNodeBs by sending crafted SCTP messages to the Cisco MME.

- **Severity:** Medium 6.8 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/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:** 26 Jan 2020
- **Updated:** 15 Nov 2024
- **Also known as:** GHSA-fhjc-mpvv-5r8g

## What is CVE-2019-16026?

CVE-2019-16026 is a medium-severity denial of service vulnerability in Cisco ASR 5000 Series Software, published on 26 Jan 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the implementation of the Stream Control Transmission Protocol (SCTP) on Cisco Mobility Management Entity (MME) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an eNodeB that is connected to an affected device. The vulnerability is due to insufficient input validation of SCTP traffic. An attacker could exploit this vulnerability by leveraging a man-in-the-middle position between the eNodeB and the MME and then sending a crafted SCTP message to the MME. A successful exploit would cause the MME to stop sending SCTP messages to the eNodeB, triggering a DoS condition.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2019-16026?

It affects 1 product.


Products: Cisco Staros.

## How do I fix CVE-2019-16026?

No fix has been published for CVE-2019-16026 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-16026 being exploited?

There is no known exploitation of CVE-2019-16026 in the wild and no public exploit code.

## Other vulnerabilities in Cisco ASR 5000 Series Software

- [CVE-2023-20046](https://insights.sbomify.com/CVE-2023-20046/): Auth bypass in Cisco ASR 5000 Series Software (high 8.8)
- [CVE-2019-1869](https://insights.sbomify.com/CVE-2019-1869/): Cisco StarOS Denial of Service Vulnerability (high 8.6)
- [CVE-2018-0369](https://insights.sbomify.com/CVE-2018-0369/): Denial of service in Cisco StarOS unknown (high 8.6)
- [CVE-2017-6707](https://insights.sbomify.com/CVE-2017-6707/): Command injection in Cisco StarOS (high 8.2)
- [CVE-2021-1539](https://insights.sbomify.com/CVE-2021-1539/): Cisco ASR 5000 Series Software Authorization Bypass Vulnerabilities (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-16026 and fix it if it is affected.

What it is: CVE-2019-16026 is a medium-severity denial of service vulnerability in Cisco ASR 5000 Series Software, published on 26 Jan 2020. 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-2019-16026 in the wild and no public exploit code.

Affected product: Cisco ASR 5000 Series 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-2019-16026/ (Markdown: https://insights.sbomify.com/CVE-2019-16026/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-16026
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-16026
- OSV: https://osv.dev/vulnerability/CVE-2019-16026

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-16026/
Summaries are generated and may contain mistakes; the official description above is the record.