# CVE-2019-1684: Denial of service in Cisco IP Phone 8800 Series Software

> An adjacent attacker can cause a temporary denial of service on Cisco IP phones by sending malicious CDP or LLDP packets.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Feb 2019
- **Updated:** 21 Nov 2024
- **Also known as:** GHSA-325p-cm4c-j6f9

## What is CVE-2019-1684?

CVE-2019-1684 is a medium-severity denial of service vulnerability in Cisco IP Phone 8800 Series Software, published on 21 Feb 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the Cisco Discovery Protocol or Link Layer Discovery Protocol (LLDP) implementation for the Cisco IP Phone 7800 and 8800 Series could allow an unauthenticated, adjacent attacker to cause an affected phone to reload unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to missing length validation of certain Cisco Discovery Protocol or LLDP packet header fields. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol or LLDP packet to the targeted phone. A successful exploit could allow the attacker to cause the affected phone to reload unexpectedly, resulting in a temporary DoS condition. Versions prior to 12.6(1)MN80 are affected.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), CWE-399

## Which versions are affected by CVE-2019-1684?

It affects 14 products.


Products: Cisco Ip Conference Phone 7832 Firmware, Cisco Ip Conference Phone 8832 Firmware, Cisco Ip Phone 7800 Firmware, Cisco Ip Phone 7811 Firmware, Cisco Ip Phone 7821 Firmware, Cisco Ip Phone 7841 Firmware, Cisco Ip Phone 7861 Firmware, Cisco Ip Phone 8800 Firmware, Cisco Ip Phone 8811 Firmware, Cisco Ip Phone 8841 Firmware, Cisco Ip Phone 8845 Firmware, Cisco Ip Phone 8851 Firmware, Cisco Ip Phone 8861 Firmware, Cisco Ip Phone 8865 Firmware.

## How do I fix CVE-2019-1684?

No fix has been published for CVE-2019-1684 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-1684 being exploited?

There is no known exploitation of CVE-2019-1684 in the wild and no public exploit code.

## Other vulnerabilities in Cisco IP Phone 8800 Series Software

- [CVE-2020-3111](https://insights.sbomify.com/CVE-2020-3111/): Cisco IP Phone Remote Code Execution and Denial of Service Vulnerability (high 8.8)
- [CVE-2019-1635](https://insights.sbomify.com/CVE-2019-1635/): Cisco IP Phone 7800 Series and 8800 Series Session Initiation Protocol XML Denial of Service Vulnerability (high 7.5)
- [CVE-2021-1379](https://insights.sbomify.com/CVE-2021-1379/): Memory corruption in Cisco IP Phones with Multiplatform Firmware (medium 6.5)
- [CVE-2021-34711](https://insights.sbomify.com/CVE-2021-34711/): Cisco IP Phone Software Arbitrary File Read Vulnerability (medium 5.5)
- [CVE-2019-1922](https://insights.sbomify.com/CVE-2019-1922/): Cisco IP Phone 7800 and 8800 Series Session Initiation Protocol Denial of Service Vulnerability (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-1684 and fix it if it is affected.

What it is: CVE-2019-1684 is a medium-severity denial of service vulnerability in Cisco IP Phone 8800 Series Software, published on 21 Feb 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-1684 in the wild and no public exploit code.

Affected product: Cisco IP Phone 8800 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-2019-1684/ (Markdown: https://insights.sbomify.com/CVE-2019-1684/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1684
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1684
- OSV: https://osv.dev/vulnerability/CVE-2019-1684

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-1684/
Summaries are generated and may contain mistakes; the official description above is the record.