# CVE-2024-20451: Denial of service in Cisco Small Business IP Phones

> Unauthenticated remote attackers can cause Cisco Small Business IP Phones to reload unexpectedly by sending crafted HTTP packets, resulting in a denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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:** 7 Aug 2024
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-3gj8-mpqg-gqrv

## What is CVE-2024-20451?

CVE-2024-20451 is a high-severity denial of service vulnerability in Cisco Small Business IP Phones, published on 7 Aug 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Multiple vulnerabilities in the web-based management interface of Cisco Small Business SPA300 Series IP Phones and Cisco Small Business SPA500 Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly.

These vulnerabilities exist because HTTP packets are not properly checked for errors. An attacker could exploit this vulnerability by sending a crafted HTTP packet to the remote interface of an affected device. A successful exploit could allow the attacker to cause a DoS condition on the device.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2024-20451?

It affects 11 products.


Products: Cisco Spa 301 Firmware, Cisco Spa 303 Firmware, Cisco Spa 501g Firmware, Cisco Spa 502g Firmware, Cisco Spa 504g Firmware, Cisco Spa 508g Firmware, Cisco Spa 509g Firmware, Cisco Spa 512g Firmware, Cisco Spa 514g Firmware, Cisco Spa 525g2 Firmware, Cisco Spa 525g Firmware.

## How do I fix CVE-2024-20451?

No fix has been published for CVE-2024-20451 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-20451 being exploited?

There is no known exploitation of CVE-2024-20451 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Small Business IP Phones

- [CVE-2024-20450](https://insights.sbomify.com/CVE-2024-20450/): Memory corruption in Cisco Small Business IP Phones (critical 9.8)
- [CVE-2024-20454](https://insights.sbomify.com/CVE-2024-20454/): Memory corruption in Cisco Small Business IP Phones (critical 9.8)
- [CVE-2017-12219](https://insights.sbomify.com/CVE-2017-12219/): Denial of service in Cisco Small Business SPA300, SPA500, and SPA51x Series IP Phones (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-20451 and fix it if it is affected.

What it is: CVE-2024-20451 is a high-severity denial of service vulnerability in Cisco Small Business IP Phones, published on 7 Aug 2024. 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-2024-20451 in the wild and no public exploit code.

Affected product: Cisco Small Business IP Phones. 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-2024-20451/ (Markdown: https://insights.sbomify.com/CVE-2024-20451/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-20451
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-20451
- OSV: https://osv.dev/vulnerability/CVE-2024-20451

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-20451/
Summaries are generated and may contain mistakes; the official description above is the record.