# CVE-2018-0340: Cross-site scripting in Cisco Unified Communications Manager unknown

> An authenticated remote attacker can execute arbitrary script code or access sensitive browser-based information via XSS in the Cisco Unified Communications Manager web interface.

- **Severity:** Medium 5.4 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 7 Jun 2018
- **Updated:** 29 Nov 2024
- **Also known as:** GHSA-h2cv-5r7r-4r2j

## What is CVE-2018-0340?

CVE-2018-0340 is a medium-severity cross-site scripting vulnerability in Cisco Unified Communications Manager, published on 7 Jun 2018. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

A vulnerability in the web framework of the Cisco Unified Communications Manager (Unified CM) software could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack against the user of the web interface of the affected system. The vulnerability is due to insufficient input validation of certain parameters passed to the web server. An attacker could exploit this vulnerability by convincing the user to access a malicious link or by intercepting the user request and injecting certain malicious code. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected site or allow the attacker to access sensitive browser-based information. Cisco Bug IDs: CSCvj00512.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2018-0340?

It affects 1 product.


Products: Cisco Unified Communications Manager.

## How do I fix CVE-2018-0340?

No fix has been published for CVE-2018-0340 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0340 being exploited?

There is no known exploitation of CVE-2018-0340 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Unified Communications Manager

- [CVE-2026-20230](https://insights.sbomify.com/CVE-2026-20230/): Cisco Unified Communications Manager Server-Side Request Forgery (SSRF) (high 8.6, exploited in the wild)
- [CVE-2026-20045](https://insights.sbomify.com/CVE-2026-20045/): Cisco Unified Communications Products Code Injection (high 8.2, exploited in the wild)
- [CVE-2025-20309](https://insights.sbomify.com/CVE-2025-20309/): Cisco Unified Communications Manager Static SSH Credentials Vulnerability (critical 10.0)
- [CVE-2011-1643](https://insights.sbomify.com/CVE-2011-1643/): Information disclosure in n/a (critical 10.0)
- [CVE-2024-20253](https://insights.sbomify.com/CVE-2024-20253/): Deserialization in Cisco Packaged Contact Center Enterprise (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-0340 and fix it if it is affected.

What it is: CVE-2018-0340 is a medium-severity cross-site scripting vulnerability in Cisco Unified Communications Manager, published on 7 Jun 2018. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2018-0340 in the wild and no public exploit code.

Affected product: Cisco Unified Communications Manager. 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-2018-0340/ (Markdown: https://insights.sbomify.com/CVE-2018-0340/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0340
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0340
- OSV: https://osv.dev/vulnerability/CVE-2018-0340

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-0340/
Summaries are generated and may contain mistakes; the official description above is the record.