# CVE-2023-20108: Denial of service in Cisco Unified Communications Manager IM and Presence Service

> An unauthenticated remote attacker can cause a denial of service by sending a crafted login message to the Cisco Unified CM IM&P authentication 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:** 28 Jun 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-8937-gcf5-34xq

## What is CVE-2023-20108?

CVE-2023-20108 is a high-severity denial of service vulnerability in Cisco Unified Communications Manager IM and Presence Service, published on 28 Jun 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the XCP Authentication Service of the Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P) could allow an unauthenticated, remote attacker to cause a temporary service outage for all Cisco Unified CM IM&P users who are attempting to authenticate to the service, resulting in a denial of service (DoS) condition.

 This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted login message to the affected device. A successful exploit could allow the attacker to cause an unexpected restart of the authentication service, preventing new users from successfully authenticating. Exploitation of this vulnerability does not impact Cisco Unified CM IM&P users who were authenticated prior to an attack.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-789 (Memory Allocation with Excessive Size Value)

## Which versions are affected by CVE-2023-20108?

It affects 1 product.


Products: Cisco Unified Communications Manager Im and Presence Service.

## How do I fix CVE-2023-20108?

No fix has been published for CVE-2023-20108 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-20108 being exploited?

There is no known exploitation of CVE-2023-20108 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Unified Communications Manager IM and Presence Service

- [CVE-2018-0363](https://insights.sbomify.com/CVE-2018-0363/): Cross-site request forgery in Cisco Unified Communications Manager IM & Presence Service unknown (high 8.8)
- [CVE-2016-6464](https://insights.sbomify.com/CVE-2016-6464/): Information disclosure in Cisco Unified Communications Manager (high 7.5)
- [CVE-2016-1466](https://insights.sbomify.com/CVE-2016-1466/): Denial of service in n/a (high 7.5)
- [CVE-2021-1363](https://insights.sbomify.com/CVE-2021-1363/): Cisco Unified Communications Manager IM & Presence Service SQL Injection Vulnerabilities (high 7.1)
- [CVE-2021-1365](https://insights.sbomify.com/CVE-2021-1365/): Cisco Unified Communications Manager IM & Presence Service SQL Injection Vulnerabilities (high 7.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-20108 and fix it if it is affected.

What it is: CVE-2023-20108 is a high-severity denial of service vulnerability in Cisco Unified Communications Manager IM and Presence Service, published on 28 Jun 2023. 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-2023-20108 in the wild and no public exploit code.

Affected product: Cisco Unified Communications Manager IM and Presence Service. 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-2023-20108/ (Markdown: https://insights.sbomify.com/CVE-2023-20108/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20108
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20108
- OSV: https://osv.dev/vulnerability/CVE-2023-20108

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From sbomify Insights: https://insights.sbomify.com/CVE-2023-20108/
Summaries are generated and may contain mistakes; the official description above is the record.