# CVE-2021-34736: Cisco Integrated Management Controller GUI Denial of Service Vulnerability

> Unauthenticated remote attackers can cause a denial of service in Cisco Integrated Management Controller by sending crafted HTTP requests.

- **Severity:** Medium 5.3 (`CVSS:3.1/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:** 21 Oct 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-q459-pjhx-263x

## What is CVE-2021-34736?

CVE-2021-34736 is a medium-severity denial of service vulnerability in Cisco Unified Computing System, published on 21 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Software could allow an unauthenticated, remote attacker to cause the web-based management interface to unexpectedly restart. The vulnerability is due to insufficient input validation on the web-based management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to cause the interface to restart, resulting in a denial of service (DoS) condition.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-34736?

It affects 1 product.


Products: Cisco Unified Computing System.

## How do I fix CVE-2021-34736?

No fix has been published for CVE-2021-34736 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34736 being exploited?

There is no known exploitation of CVE-2021-34736 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Unified Computing System

- [CVE-2026-20200](https://insights.sbomify.com/CVE-2026-20200/): Cisco Integrated Management Controller Argument Injection and Remote Code Execution Vulnerability (high 8.8)
- [CVE-2026-20094](https://insights.sbomify.com/CVE-2026-20094/): Cisco Integrated Management Controller Command Injection Vulnerability (high 8.8)
- [CVE-2018-0430](https://insights.sbomify.com/CVE-2018-0430/): Cisco Integrated Management Controller Command Injection Vulnerability (high 8.8)
- [CVE-2018-0431](https://insights.sbomify.com/CVE-2018-0431/): Cisco Integrated Management Controller Command Injection Vulnerability (high 8.8)
- [CVE-2012-4078](https://insights.sbomify.com/CVE-2012-4078/): Auth bypass in n/a (high 8.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34736 and fix it if it is affected.

What it is: CVE-2021-34736 is a medium-severity denial of service vulnerability in Cisco Unified Computing System, published on 21 Oct 2021. 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-2021-34736 in the wild and no public exploit code.

Affected product: Cisco Unified Computing System. 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-2021-34736/ (Markdown: https://insights.sbomify.com/CVE-2021-34736/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34736
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34736
- OSV: https://osv.dev/vulnerability/CVE-2021-34736

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-34736/
Summaries are generated and may contain mistakes; the official description above is the record.