# CVE-2026-20178: Open redirect in Cisco Webex App

> An attacker can redirect users to malicious websites via crafted URLs in the Cisco Webex App browser interface.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 17 Jun 2026
- **Updated:** 17 Jun 2026
- **Also known as:** GHSA-5m7h-7whv-78fw

## What is CVE-2026-20178?

CVE-2026-20178 is a medium-severity vulnerability in Cisco Webex App, published on 17 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A vulnerability in the browser-based version of Cisco Webex App could have allowed an unauthenticated, remote attacker to redirect users to a malicious webpage. Cisco has addressed this vulnerability in the Cisco Webex App, and no customer action is needed.

 This vulnerability existed due to improper input validation of URL parameters in an HTTP request. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerability by persuading a user to click a crafted URL. A successful exploit could have allowed the attacker to redirect a user to a malicious website.

Weakness: CWE-601 (URL Redirection to Untrusted Site)

## Which versions are affected by CVE-2026-20178?

It affects 1 product.


Products: Cisco Webex Web App.

## How do I fix CVE-2026-20178?

No fix has been published for CVE-2026-20178 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-20178 being exploited?

There is no known exploitation of CVE-2026-20178 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-20178 and fix it if it is affected.

What it is: CVE-2026-20178 is a medium-severity vulnerability in Cisco Webex App, published on 17 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-20178 in the wild and no public exploit code.

Affected product: Cisco Webex App. 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-2026-20178/ (Markdown: https://insights.sbomify.com/CVE-2026-20178/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-20178
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-20178
- OSV: https://osv.dev/vulnerability/CVE-2026-20178

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-20178/
Summaries are generated and may contain mistakes; the official description above is the record.