# CVE-2021-1266: Cisco Managed Services Accelerator Denial of Service Vulnerability

> An authenticated remote attacker can cause a denial of service on Cisco MSX by flooding the REST API with crafted requests.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L`)
- **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:** 4 Feb 2021
- **Updated:** 8 Nov 2024
- **Also known as:** GHSA-q2xf-jvwq-327h

## What is CVE-2021-1266?

CVE-2021-1266 is a medium-severity denial of service vulnerability in Cisco Managed Services Accelerator, published on 4 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability in the REST API of Cisco Managed Services Accelerator (MSX) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to the way that the affected software logs certain API requests. An attacker could exploit this vulnerability by sending a flood of crafted API requests to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2021-1266?

It affects 1 product.


Products: Cisco Managed Services Accelerator.

## How do I fix CVE-2021-1266?

No fix has been published for CVE-2021-1266 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1266 being exploited?

There is no known exploitation of CVE-2021-1266 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Managed Services Accelerator

- [CVE-2019-15974](https://insights.sbomify.com/CVE-2019-15974/): Cisco Managed Services Accelerator Open Redirect Vulnerability (medium 4.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1266 and fix it if it is affected.

What it is: CVE-2021-1266 is a medium-severity denial of service vulnerability in Cisco Managed Services Accelerator, published on 4 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-1266 in the wild and no public exploit code.

Affected product: Cisco Managed Services Accelerator. 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-2021-1266/ (Markdown: https://insights.sbomify.com/CVE-2021-1266/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1266
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1266
- OSV: https://osv.dev/vulnerability/CVE-2021-1266

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1266/
Summaries are generated and may contain mistakes; the official description above is the record.