# CVE-2019-1845: Denial of service in Cisco TelePresence Video Communication Server (VCS)

> Unauthenticated remote attackers can cause a denial of service by sending malformed XMPP requests, disrupting user authentication in Cisco Unified Communications products.

- **Severity:** High 8.6 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/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:** 5 Jun 2019
- **Updated:** 19 Nov 2024
- **Also known as:** GHSA-qfgg-fv6m-h7j6

## What is CVE-2019-1845?

CVE-2019-1845 is a high-severity denial of service vulnerability in Cisco TelePresence Video Communication Server (VCS), published on 5 Jun 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the authentication service of the Cisco Unified Communications Manager IM and Presence (Unified CM IM&P) Service, Cisco TelePresence Video Communication Server (VCS), and Cisco Expressway Series could allow an unauthenticated, remote attacker to cause a service outage for users attempting to authenticate, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient controls for specific memory operations. An attacker could exploit this vulnerability by sending a malformed Extensible Messaging and Presence Protocol (XMPP) authentication request to an affected system. A successful exploit could allow the attacker to cause an unexpected restart of the authentication service, preventing users from successfully authenticating. Exploitation of this vulnerability does not impact users who were authenticated prior to an attack.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2019-1845?

It affects 2 products.


Products: Cisco Telepresence Video Communication Server, Cisco Unified Communications Manager Im and Presence Service.

## How do I fix CVE-2019-1845?

No fix has been published for CVE-2019-1845 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-1845 being exploited?

There is no known exploitation of CVE-2019-1845 in the wild and no public exploit code.

## Other vulnerabilities in Cisco TelePresence Video Communication Server (VCS)

- [CVE-2023-20105](https://insights.sbomify.com/CVE-2023-20105/): Privilege escalation in Cisco TelePresence Video Communication Server (VCS) Expressway (critical 9.6)
- [CVE-2023-20192](https://insights.sbomify.com/CVE-2023-20192/): Cisco Expressway Series and Cisco TelePresence Video Communication Server Privilege Escalation Vulnerabilities (critical 9.6)
- [CVE-2022-20754](https://insights.sbomify.com/CVE-2022-20754/): Cisco Expressway Series and Cisco TelePresence Video Communication Server Vulnerabilities (critical 9.0)
- [CVE-2022-20755](https://insights.sbomify.com/CVE-2022-20755/): Cisco Expressway Series and Cisco TelePresence Video Communication Server Vulnerabilities (critical 9.0)
- [CVE-2016-1468](https://insights.sbomify.com/CVE-2016-1468/): Command injection in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-1845 and fix it if it is affected.

What it is: CVE-2019-1845 is a high-severity denial of service vulnerability in Cisco TelePresence Video Communication Server (VCS), published on 5 Jun 2019. 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-2019-1845 in the wild and no public exploit code.

Affected product: Cisco TelePresence Video Communication Server (VCS). 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-2019-1845/ (Markdown: https://insights.sbomify.com/CVE-2019-1845/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1845
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1845
- OSV: https://osv.dev/vulnerability/CVE-2019-1845

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-1845/
Summaries are generated and may contain mistakes; the official description above is the record.